Vendor import of less v551.vendor/less/v551

69 files changed, 1746 insertions, 717 deletions

diff --git a/LICENSE b/LICENSE
index 832ca1b37075..315d1d86815c 100644
--- a/LICENSE
+++ b/LICENSE
@@ -2,7 +2,7 @@
                           ------------
 
 Less
-Copyright (C) 1984-2016  Mark Nudelman
+Copyright (C) 1984-2018  Mark Nudelman
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions
diff --git a/Makefile.aut b/Makefile.aut
index 8816902220b3..f16642ce25a6 100644
--- a/Makefile.aut
+++ b/Makefile.aut
@@ -112,6 +112,13 @@ ubin.uni: unicode/UnicodeData.txt
 wide.uni: unicode/EastAsianWidth.txt
 	./mkutable -f1 W F -- unicode/EastAsianWidth.txt > $@
 
+unicode/UnicodeData.txt:
+	mkdir -p unicode
+	curl -s -o $@ ftp://ftp.unicode.org/Public/UNIDATA/UnicodeData.txt
+unicode/EastAsianWidth.txt:
+	mkdir -p unicode
+	curl -s -o $@ ftp://ftp.unicode.org/Public/UNIDATA/EastAsianWidth.txt
+
 distfiles: ${DISTFILES}
 
 dist: ${DISTFILES}
@@ -137,4 +144,4 @@ dist: ${DISTFILES}
 tagall:
 	@REL=`sed -e '/char version/!d' -e 's/[^0-9.]*\([0-9.]*\).*/v\1/' -e q ${srcdir}/version.c`; \
 	echo "tagging $$REL"; \
-	$(GIT) tag -f "$$REL"
+	$(GIT) tag -a -f -m "$$REL" "$$REL"
diff --git a/NEWS b/NEWS
index 14997c253734..24d74af4da2d 100644
--- a/NEWS
+++ b/NEWS
@@ -11,6 +11,38 @@
 
 ======================================================================
 
+	Major changes between "less" versions 530 and 551
+
+* Add --mouse option.
+
+* Add --wheel-lines option.
+
+* Add --no-histdups option.
+
+* Add --save-marks option.
+
+* Support PCRE2 regular expression library.
+
+* Redraw screen on SIGWINCH even if screen size doesn't change.
+
+* Shell-escape filenames in history so they can be used again.
+
+* Ring bell if user enters invalid long option name.
+
+* Use PCRE_UTF8 flag for pcre regular expressions when in UTF-8 mode.
+
+* Windows: use wide-char string to set console title.
+
+* Don't count lines in initial screen if using -X with -F.
+
+* Support mingw build system.
+
+* Fix bug in v command on empty file.
+
+* Fix bug in v command when filename contains shell metacharacters.
+
+======================================================================
+
 	Major changes between "less" versions 487 and 530
 
 * Don't output terminal init sequence if using -F and file fits on one screen.
diff --git a/README b/README
index 9103598ff1c2..682cdc5faef5 100644
--- a/README
+++ b/README
@@ -1,7 +1,7 @@
 
-                            Less, version 530
+                            Less, version 551
 
-    This is the distribution of less, version 530, released 05 Dec 2017.
+    This is the distribution of less, version 551, released 11 Jun 2019.
     This program is part of the GNU project (http://www.gnu.org).
 
     This program is free software.  You may redistribute it and/or
@@ -48,6 +48,7 @@ INSTALLATION (Unix systems only):
      finds a regular expression library automatically.  Other values are:
         gnu            Use the GNU regex library.
         pcre           Use the PCRE library.
+        pcre2          Use the PCRE2 library.
         posix          Use the POSIX-compatible regcomp.
         regcmp         Use the regcmp library.
         re_comp        Use the re_comp library.
@@ -55,6 +56,7 @@ INSTALLATION (Unix systems only):
         regcomp-local  Use Henry Spencer's V8-compatible regcomp
                        (source is supplied with less).
         none           No regular expressions, only simple string matching.
+
    --with-secure
      Builds a "secure" version of less, with some features disabled
      to prevent users from viewing other files, accessing shell
diff --git a/brac.c b/brac.c
index 44f240361cbd..cea4a2bd6857 100644
--- a/brac.c
+++ b/brac.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
diff --git a/ch.c b/ch.c
index 47c1a32350f5..636f68f00791 100644
--- a/ch.c
+++ b/ch.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -144,7 +144,7 @@ static int ch_addbuf();
  * Get the character pointed to by the read pointer.
  */
 	int
-ch_get()
+ch_get(VOID_PARAM)
 {
 	struct buf *bp;
 	struct bufnode *bn;
@@ -392,7 +392,7 @@ ch_ungetchar(c)
  * If we haven't read all of standard input into it, do that now.
  */
 	public void
-end_logfile()
+end_logfile(VOID_PARAM)
 {
 	static int tried = FALSE;
 
@@ -417,7 +417,7 @@ end_logfile()
  * Write all the existing buffered data to the log file.
  */
 	public void
-sync_logfile()
+sync_logfile(VOID_PARAM)
 {
 	struct buf *bp;
 	struct bufnode *bn;
@@ -515,7 +515,7 @@ ch_seek(pos)
  * Seek to the end of the file.
  */
 	public int
-ch_end_seek()
+ch_end_seek(VOID_PARAM)
 {
 	POSITION len;
 
@@ -542,7 +542,7 @@ ch_end_seek()
  * Seek to the last position in the file that is currently buffered.
  */
 	public int
-ch_end_buffer_seek()
+ch_end_buffer_seek(VOID_PARAM)
 {
 	struct buf *bp;
 	struct bufnode *bn;
@@ -570,7 +570,7 @@ ch_end_buffer_seek()
  * beginning of the pipe is no longer buffered.
  */
 	public int
-ch_beg_seek()
+ch_beg_seek(VOID_PARAM)
 {
 	struct bufnode *bn;
 	struct bufnode *firstbn;
@@ -602,7 +602,7 @@ ch_beg_seek()
  * Return the length of the file, if known.
  */
 	public POSITION
-ch_length()
+ch_length(VOID_PARAM)
 {
 	if (thisfile == NULL)
 		return (NULL_POSITION);
@@ -619,7 +619,7 @@ ch_length()
  * Return the current position in the file.
  */
 	public POSITION
-ch_tell()
+ch_tell(VOID_PARAM)
 {
 	if (thisfile == NULL)
 		return (NULL_POSITION);
@@ -630,7 +630,7 @@ ch_tell()
  * Get the current char and post-increment the read pointer.
  */
 	public int
-ch_forw_get()
+ch_forw_get(VOID_PARAM)
 {
 	int c;
 
@@ -653,7 +653,7 @@ ch_forw_get()
  * Pre-decrement the read pointer and get the new current char.
  */
 	public int
-ch_back_get()
+ch_back_get(VOID_PARAM)
 {
 	if (thisfile == NULL)
 		return (EOI);
@@ -693,7 +693,7 @@ ch_setbufspace(bufspace)
  * Flush (discard) any saved file state, including buffer contents.
  */
 	public void
-ch_flush()
+ch_flush(VOID_PARAM)
 {
 	struct bufnode *bn;
 
@@ -760,7 +760,7 @@ ch_flush()
  * The buffer is added to the tail of the buffer chain.
  */
 	static int
-ch_addbuf()
+ch_addbuf(VOID_PARAM)
 {
 	struct buf *bp;
 	struct bufnode *bn;
@@ -785,7 +785,7 @@ ch_addbuf()
  *
  */
 	static void
-init_hashtbl()
+init_hashtbl(VOID_PARAM)
 {
 	int h;
 
@@ -800,7 +800,7 @@ init_hashtbl()
  * Delete all buffers for this file.
  */
 	static void
-ch_delbufs()
+ch_delbufs(VOID_PARAM)
 {
 	struct bufnode *bn;
 
@@ -840,7 +840,7 @@ seekable(f)
  * This is used after an ignore_eof read, during which the EOF may change.
  */
 	public void
-ch_set_eof()
+ch_set_eof(VOID_PARAM)
 {
 	ch_fsize = ch_fpos;
 }
@@ -890,7 +890,7 @@ ch_init(f, flags)
  * Close a filestate.
  */
 	public void
-ch_close()
+ch_close(VOID_PARAM)
 {
 	int keepstate = FALSE;
 
@@ -933,7 +933,7 @@ ch_close()
  * Return ch_flags for the current file.
  */
 	public int
-ch_getflags()
+ch_getflags(VOID_PARAM)
 {
 	if (thisfile == NULL)
 		return (0);
diff --git a/charset.c b/charset.c
index 88978918e45f..5441952a0db5 100644
--- a/charset.c
+++ b/charset.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -245,7 +245,7 @@ icharset(name, no_error)
  * Define a charset, given a locale name.
  */
 	static void
-ilocale()
+ilocale(VOID_PARAM)
 {
 	int c;
 
@@ -315,7 +315,7 @@ setfmt(s, fmtvarptr, attrptr, default_fmt)
  *
  */
 	static void
-set_charset()
+set_charset(VOID_PARAM)
 {
 	char *s;
 
@@ -338,7 +338,7 @@ set_charset()
 	 * LESSCHARSET is not defined: try LESSCHARDEF.
 	 */
 	s = lgetenv("LESSCHARDEF");
-	if (s != NULL && *s != '\0')
+	if (!isnullenv(s))
 	{
 		ichardef(s);
 		return;
@@ -395,7 +395,7 @@ set_charset()
  * Initialize charset data structures.
  */
 	public void
-init_charset()
+init_charset(VOID_PARAM)
 {
 	char *s;
 
diff --git a/charset.h b/charset.h
index 1e3f0691069a..500309131332 100644
--- a/charset.h
+++ b/charset.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
diff --git a/cmd.h b/cmd.h
index 632b65ea3c4e..8ea178309a65 100644
--- a/cmd.h
+++ b/cmd.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -71,6 +71,13 @@
 #define A_RRSHIFT              59
 #define A_CLRMARK              62
 #define A_SETMARKBOT           63
+#define A_X11MOUSE_IN          64
+#define A_X11MOUSE_IGNORE      65
+#define A_F_MOUSE              66
+#define A_B_MOUSE              67
+/* Note "X116" refers to extended (1006) X11 mouse reporting. */
+#define A_X116MOUSE_IN         68
+#define A_X116MOUSE_IGNORE     69
 
 #define A_INVALID              100
 #define A_NOACTION             101
diff --git a/cmdbuf.c b/cmdbuf.c
index db5b2595f9a5..0648aecb7075 100644
--- a/cmdbuf.c
+++ b/cmdbuf.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -22,6 +22,8 @@
 
 extern int sc_width;
 extern int utf_mode;
+extern int no_hist_dups;
+extern int marks_modified;
 
 static char cmdbuf[CMDBUF_SIZE]; /* Buffer for holding a multi-char command */
 static int cmd_col;		/* Current column of the cursor */
@@ -58,6 +60,7 @@ public char closequote = '"';
 #define HISTFILE_FIRST_LINE      ".less-history-file:"
 #define HISTFILE_SEARCH_SECTION  ".search"
 #define HISTFILE_SHELL_SECTION   ".shell"
+#define HISTFILE_MARK_SECTION    ".mark"
 
 /*
  * A mlist structure represents a command history.
@@ -114,7 +117,7 @@ static int cmd_mbc_buf_index;
  * Reset command buffer (to empty).
  */
 	public void
-cmd_reset()
+cmd_reset(VOID_PARAM)
 {
 	cp = cmdbuf;
 	*cp = '\0';
@@ -129,7 +132,7 @@ cmd_reset()
  * Clear command line.
  */
 	public void
-clear_cmd()
+clear_cmd(VOID_PARAM)
 {
 	cmd_col = prompt_col = 0;
 	cmd_mbc_buf_len = 0;
@@ -169,7 +172,7 @@ cmd_putstr(s)
  * How many characters are in the command buffer?
  */
 	public int
-len_cmdbuf()
+len_cmdbuf(VOID_PARAM)
 {
 	char *s = cmdbuf;
 	char *endline = s + strlen(s);
@@ -302,7 +305,7 @@ cmd_repaint(old_cp)
  * and set cp to the corresponding char in cmdbuf.
  */
 	static void
-cmd_home()
+cmd_home(VOID_PARAM)
 {
 	while (cmd_col > prompt_col)
 	{
@@ -321,7 +324,7 @@ cmd_home()
  * Shift the cmdbuf display left a half-screen.
  */
 	static void
-cmd_lshift()
+cmd_lshift(VOID_PARAM)
 {
 	char *s;
 	char *save_cp;
@@ -359,7 +362,7 @@ cmd_lshift()
  * Shift the cmdbuf display right a half-screen.
  */
 	static void
-cmd_rshift()
+cmd_rshift(VOID_PARAM)
 {
 	char *s;
 	char *save_cp;
@@ -389,7 +392,7 @@ cmd_rshift()
  * Move cursor right one character.
  */
 	static int
-cmd_right()
+cmd_right(VOID_PARAM)
 {
 	char *pr;
 	char *ncp;
@@ -424,7 +427,7 @@ cmd_right()
  * Move cursor left one character.
  */
 	static int
-cmd_left()
+cmd_left(VOID_PARAM)
 {
 	char *ncp;
 	int width = 0;
@@ -492,7 +495,7 @@ cmd_ichar(cs, clen)
  * Delete the char to the left of the cursor.
  */
 	static int
-cmd_erase()
+cmd_erase(VOID_PARAM)
 {
 	char *s;
 	int clen;
@@ -541,7 +544,7 @@ cmd_erase()
  * Delete the char under the cursor.
  */
 	static int
-cmd_delete()
+cmd_delete(VOID_PARAM)
 {
 	if (*cp == '\0')
 	{
@@ -560,7 +563,7 @@ cmd_delete()
  * Delete the "word" to the left of the cursor.
  */
 	static int
-cmd_werase()
+cmd_werase(VOID_PARAM)
 {
 	if (cp > cmdbuf && cp[-1] == ' ')
 	{
@@ -586,7 +589,7 @@ cmd_werase()
  * Delete the "word" under the cursor.
  */
 	static int
-cmd_wdelete()
+cmd_wdelete(VOID_PARAM)
 {
 	if (*cp == ' ')
 	{
@@ -612,7 +615,7 @@ cmd_wdelete()
  * Delete all chars in the command buffer.
  */
 	static int
-cmd_kill()
+cmd_kill(VOID_PARAM)
 {
 	if (cmdbuf[0] == '\0')
 	{
@@ -702,6 +705,7 @@ cmd_updown(action)
 			s = ml->string;
 			if (s == NULL)
 				s = "";
+			cmd_offset = 0;
 			cmd_home();
 			clear_eol();
 			strcpy(cmdbuf, s);
@@ -719,6 +723,31 @@ cmd_updown(action)
 #endif
 
 /*
+ *
+ */
+	static void
+ml_link(mlist, ml)
+	struct mlist *mlist;
+	struct mlist *ml;
+{
+	ml->next = mlist;
+	ml->prev = mlist->prev;
+	mlist->prev->next = ml;
+	mlist->prev = ml;
+}
+
+/*
+ *
+ */
+	static void
+ml_unlink(ml)
+	struct mlist *ml;
+{
+	ml->prev->next = ml->next;
+	ml->next->prev = ml->prev;
+}
+
+/*
  * Add a string to an mlist.
  */
 	public void
@@ -736,6 +765,21 @@ cmd_addhist(mlist, cmd, modified)
 	if (strlen(cmd) == 0)
 		return;
 
+	if (no_hist_dups)
+	{
+		struct mlist *next = NULL;
+		for (ml = mlist->next;  ml->string != NULL;  ml = next)
+		{
+			next = ml->next;
+			if (strcmp(ml->string, cmd) == 0)
+			{
+				ml_unlink(ml);
+				free(ml->string);
+				free(ml);
+			}
+		}
+	}
+
 	/*
 	 * Save the command unless it's a duplicate of the
 	 * last command in the history.
@@ -750,10 +794,7 @@ cmd_addhist(mlist, cmd, modified)
 		ml = (struct mlist *) ecalloc(1, sizeof(struct mlist));
 		ml->string = save(cmd);
 		ml->modified = modified;
-		ml->next = mlist;
-		ml->prev = mlist->prev;
-		mlist->prev->next = ml;
-		mlist->prev = ml;
+		ml_link(mlist, ml);
 	}
 	/*
 	 * Point to the cmd just after the just-accepted command.
@@ -768,13 +809,13 @@ cmd_addhist(mlist, cmd, modified)
  * Add it to the currently selected history list.
  */
 	public void
-cmd_accept()
+cmd_accept(VOID_PARAM)
 {
 #if CMD_HISTORY
 	/*
 	 * Nothing to do if there is no currently selected history list.
 	 */
-	if (curr_mlist == NULL)
+	if (curr_mlist == NULL || curr_mlist == ml_examine)
 		return;
 	cmd_addhist(curr_mlist, cmdbuf, 1);
 	curr_mlist->modified = 1;
@@ -799,7 +840,7 @@ cmd_edit(c)
 #if TAB_COMPLETE_FILENAME
 #define	not_in_completion()	in_completion = 0
 #else
-#define	not_in_completion()
+#define	not_in_completion(VOID_PARAM)
 #endif
 	
 	/*
@@ -934,7 +975,7 @@ cmd_istr(str)
  * cursor at the end of the word.
  */
 	static char *
-delimit_word()
+delimit_word(VOID_PARAM)
 {
 	char *word;
 #if SPACES_IN_FILENAMES
@@ -1021,7 +1062,7 @@ delimit_word()
  * which start with that word, and set tk_text to that list.
  */
 	static void
-init_compl()
+init_compl(VOID_PARAM)
 {
 	char *word;
 	char c;
@@ -1148,9 +1189,9 @@ cmd_complete(action)
 		tk_trial = next_compl(action, tk_trial);
 	}
 	
-  	/*
-  	 * Remove the original word, or the previous trial completion.
-  	 */
+	/*
+	 * Remove the original word, or the previous trial completion.
+	 */
 	while (cp > tk_ipoint)
 		(void) cmd_erase();
 	
@@ -1323,7 +1364,7 @@ cmd_int(frac)
  * Return a pointer to the command buffer.
  */
 	public char *
-get_cmdbuf()
+get_cmdbuf(VOID_PARAM)
 {
 	return (cmdbuf);
 }
@@ -1333,7 +1374,7 @@ get_cmdbuf()
  * Return the last (most recent) string in the current command history.
  */
 	public char *
-cmd_lastpattern()
+cmd_lastpattern(VOID_PARAM)
 {
 	if (curr_mlist == NULL)
 		return (NULL);
@@ -1358,7 +1399,7 @@ mlist_size(ml)
  * Get the name of the history file.
  */
 	static char *
-histfile_name()
+histfile_name(VOID_PARAM)
 {
 	char *home;
 	char *name;
@@ -1366,7 +1407,7 @@ histfile_name()
 	
 	/* See if filename is explicitly specified by $LESSHISTFILE. */
 	name = lgetenv("LESSHISTFILE");
-	if (name != NULL && *name != '\0')
+	if (!isnullenv(name))
 	{
 		if (strcmp(name, "-") == 0 || strcmp(name, "/dev/null") == 0)
 			/* $LESSHISTFILE == "-" means don't use a history file. */
@@ -1380,11 +1421,11 @@ histfile_name()
 
 	/* Otherwise, file is in $HOME. */
 	home = lgetenv("HOME");
-	if (home == NULL || *home == '\0')
+	if (isnullenv(home))
 	{
 #if OS2
 		home = lgetenv("INIT");
-		if (home == NULL || *home == '\0')
+		if (isnullenv(home))
 #endif
 			return (NULL);
 	}
@@ -1447,6 +1488,9 @@ read_cmdhist2(action, uparam, skip_search, skip_shell)
 			ml = NULL;
 			skip = NULL;
 #endif
+		} else if (strcmp(line, HISTFILE_MARK_SECTION) == 0)
+		{
+			ml = NULL;
 		} else if (*line == '"')
 		{
 			if (ml != NULL)
@@ -1456,6 +1500,9 @@ read_cmdhist2(action, uparam, skip_search, skip_shell)
 				else
 					(*action)(uparam, ml, line+1);
 			}
+		} else if (*line == 'm')
+		{
+			(*action)(uparam, NULL, line);
 		}
 	}
 	fclose(f);
@@ -1475,9 +1522,10 @@ read_cmdhist(action, uparam, skip_search, skip_shell)
 	static void
 addhist_init(void *uparam, struct mlist *ml, char *string)
 {
-	if (ml == NULL || string == NULL)
-		return;
-	cmd_addhist(ml, string, 0);
+	if (ml != NULL)
+		cmd_addhist(ml, string, 0);
+	else if (string != NULL)
+		restore_mark(string);
 }
 #endif /* CMD_HISTORY */
 
@@ -1485,7 +1533,7 @@ addhist_init(void *uparam, struct mlist *ml, char *string)
  * Initialize history from a .lesshist file.
  */
 	public void
-init_cmdhist()
+init_cmdhist(VOID_PARAM)
 {
 #if CMD_HISTORY
 	read_cmdhist(&addhist_init, NULL, 0, 0);
@@ -1558,7 +1606,7 @@ copy_hist(void *uparam, struct mlist *ml, char *string)
 {
 	struct save_ctx *ctx = (struct save_ctx *) uparam;
 
-	if (ml != ctx->mlist) {
+	if (ml != NULL && ml != ctx->mlist) {
 		/* We're changing mlists. */
 		if (ctx->mlist)
 			/* Append any new entries to the end of the current mlist. */
@@ -1567,12 +1615,8 @@ copy_hist(void *uparam, struct mlist *ml, char *string)
 		ctx->mlist = ml;
 		write_mlist_header(ctx->mlist, ctx->fout);
 	}
-	if (string != NULL)
-	{
-		/* Copy the entry. */
-		fprintf(ctx->fout, "\"%s\n", string);
-	}
-	if (ml == NULL) /* End of file */
+
+	if (string == NULL) /* End of file */
 	{
 		/* Write any sections that were not in the original file. */
 		if (mlist_search.modified)
@@ -1587,7 +1631,12 @@ copy_hist(void *uparam, struct mlist *ml, char *string)
 			write_mlist(&mlist_shell, ctx->fout);
 		}
 #endif
+	} else if (ml != NULL)
+	{
+		/* Copy mlist entry. */
+		fprintf(ctx->fout, "\"%s\n", string);
 	}
+	/* Skip marks */
 }
 #endif /* CMD_HISTORY */
 
@@ -1616,7 +1665,7 @@ make_file_private(f)
  * Does the history file need to be updated?
  */
 	static int
-histfile_modified()
+histfile_modified(VOID_PARAM)
 {
 	if (mlist_search.modified)
 		return 1;
@@ -1624,6 +1673,10 @@ histfile_modified()
 	if (mlist_shell.modified)
 		return 1;
 #endif
+#if CMD_HISTORY
+	if (marks_modified)
+		return 1;
+#endif
 	return 0;
 }
 
@@ -1631,7 +1684,7 @@ histfile_modified()
  * Update the .lesshst file.
  */
 	public void
-save_cmdhist()
+save_cmdhist(VOID_PARAM)
 {
 #if CMD_HISTORY
 	char *histname;
@@ -1665,7 +1718,8 @@ save_cmdhist()
 		fprintf(fout, "%s\n", HISTFILE_FIRST_LINE);
 		ctx.fout = fout;
 		ctx.mlist = NULL;
-		read_cmdhist(copy_hist, &ctx, skip_search, skip_shell);
+		read_cmdhist(&copy_hist, &ctx, skip_search, skip_shell);
+		save_marks(fout, HISTFILE_MARK_SECTION);
 		fclose(fout);
 #if MSDOS_COMPILER==WIN32C
 		/*
diff --git a/command.c b/command.c
index 4338b3d33f6e..6c89ca39227f 100644
--- a/command.c
+++ b/command.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -47,6 +47,7 @@ extern struct scrpos initial_scrpos;
 extern IFILE curr_ifile;
 extern void *ml_search;
 extern void *ml_examine;
+extern int wheel_lines;
 #if SHELL_ESCAPE || PIPEC
 extern void *ml_shell;
 #endif
@@ -58,6 +59,9 @@ extern int screen_trashed;	/* The screen has been overwritten */
 extern int shift_count;
 extern int oldbot;
 extern int forw_prompt;
+#if MSDOS_COMPILER==WIN32C
+extern int utf_mode;
+#endif
 
 #if SHELL_ESCAPE
 static char *shellcmd = NULL;	/* For holding last shell command for "!!" */
@@ -92,14 +96,39 @@ static void multi_search();
  * updating the screen.
  */
 	static void
-cmd_exec()
+cmd_exec(VOID_PARAM)
 {
-    clear_attn();
+	clear_attn();
 	clear_bot();
 	flush();
 }
 
 /*
+ * Indicate we are reading a multi-character command.
+ */
+	static void
+set_mca(action)
+	int action;
+{
+	mca = action;
+	deinit_mouse(); /* we don't want mouse events while entering a cmd */
+	clear_bot();
+	clear_cmd();
+}
+
+/*
+ * Indicate we are not reading a multi-character command.
+ */
+	static void
+clear_mca(VOID_PARAM)
+{
+	if (mca == 0)
+		return;
+	mca = 0;
+	init_mouse();
+}
+
+/*
  * Set up the display to start a new multi-character command.
  */
 	static void
@@ -109,15 +138,13 @@ start_mca(action, prompt, mlist, cmdflags)
 	void *mlist;
 	int cmdflags;
 {
-	mca = action;
-	clear_bot();
-	clear_cmd();
+	set_mca(action);
 	cmd_putstr(prompt);
 	set_mlist(mlist, cmdflags);
 }
 
 	public int
-in_mca()
+in_mca(VOID_PARAM)
 {
 	return (mca != 0 && mca != A_PREFIX);
 }
@@ -126,20 +153,17 @@ in_mca()
  * Set up the display to start a new search command.
  */
 	static void
-mca_search()
+mca_search(VOID_PARAM)
 {
 #if HILITE_SEARCH
 	if (search_type & SRCH_FILTER)
-		mca = A_FILTER;
+		set_mca(A_FILTER);
 	else 
 #endif
 	if (search_type & SRCH_FORW)
-		mca = A_F_SEARCH;
+		set_mca(A_F_SEARCH);
 	else
-		mca = A_B_SEARCH;
-
-	clear_bot();
-	clear_cmd();
+		set_mca(A_B_SEARCH);
 
 	if (search_type & SRCH_NO_MATCH)
 		cmd_putstr("Non-match ");
@@ -169,7 +193,7 @@ mca_search()
  * Set up the display to start a new toggle-option command.
  */
 	static void
-mca_opt_toggle()
+mca_opt_toggle(VOID_PARAM)
 {
 	int no_prompt;
 	int flag;
@@ -179,9 +203,7 @@ mca_opt_toggle()
 	flag = (optflag & ~OPT_NO_PROMPT);
 	dash = (flag == OPT_NO_TOGGLE) ? "_" : "-";
 
-	mca = A_OPT_TOGGLE;
-	clear_bot();
-	clear_cmd();
+	set_mca(A_OPT_TOGGLE);
 	cmd_putstr(dash);
 	if (optgetname)
 		cmd_putstr(dash);
@@ -204,7 +226,7 @@ mca_opt_toggle()
  * Execute a multicharacter command.
  */
 	static void
-exec_mca()
+exec_mca(VOID_PARAM)
 {
 	char *cbuf;
 
@@ -371,6 +393,7 @@ mca_opt_nonfirst_char(c)
 {
 	char *p;
 	char *oname;
+	int err;
 
 	if (curropt != NULL)
 	{
@@ -390,7 +413,8 @@ mca_opt_nonfirst_char(c)
 		return (MCA_DONE);
 	p = get_cmdbuf();
 	opt_lower = ASCII_IS_LOWER(p[0]);
-	curropt = findopt_name(&p, &oname, NULL);
+	err = 0;
+	curropt = findopt_name(&p, &oname, &err);
 	if (curropt != NULL)
 	{
 		/*
@@ -408,6 +432,9 @@ mca_opt_nonfirst_char(c)
 			if (cmd_char(c) != CC_OK)
 				return (MCA_DONE);
 		}
+	} else if (err != OPT_AMBIG)
+	{
+		bell();
 	}
 	return (MCA_MORE);
 }
@@ -459,6 +486,7 @@ mca_opt_char(c)
 			error("There is no %s option", &parg);
 			return (MCA_DONE);
 		}
+		opt_lower = ASCII_IS_LOWER(c);
 	}
 	/*
 	 * If the option which was entered does not take a 
@@ -468,7 +496,7 @@ mca_opt_char(c)
 	if ((optflag & ~OPT_NO_PROMPT) != OPT_TOGGLE ||
 	    !opt_has_param(curropt))
 	{
-		toggle_option(curropt, ASCII_IS_LOWER(c), "", optflag);
+		toggle_option(curropt, opt_lower, "", optflag);
 		return (MCA_DONE);
 	}
 	/*
@@ -571,7 +599,7 @@ mca_char(c)
 			 * as a normal command character.
 			 */
 			number = cmd_int(&fraction);
-			mca = 0;
+			clear_mca();
 			cmd_accept();
 			return (NO_MCA);
 		}
@@ -638,7 +666,7 @@ mca_char(c)
  * Discard any buffered file data.
  */
 	static void
-clear_buffers()
+clear_buffers(VOID_PARAM)
 {
 	if (!(ch_getflags() & CH_CANSEEK))
 		return;
@@ -653,7 +681,7 @@ clear_buffers()
  * Make sure the screen is displayed.
  */
 	static void
-make_display()
+make_display(VOID_PARAM)
 {
 	/*
 	 * If nothing is displayed yet, display starting from initial_scrpos.
@@ -693,7 +721,7 @@ make_display()
  * Display the appropriate prompt.
  */
 	static void
-prompt()
+prompt(VOID_PARAM)
 {
 	constant char *p;
 
@@ -733,8 +761,14 @@ prompt()
 	 * In Win32, display the file name in the window title.
 	 */
 	if (!(ch_getflags() & CH_HELPFILE))
-		SetConsoleTitle(pr_expand("Less?f - %f.", 0));
+	{
+		WCHAR w[MAX_PATH+16];
+		p = pr_expand("Less?f - %f.", 0);
+		MultiByteToWideChar(CP_ACP, 0, p, -1, w, sizeof(w)/sizeof(*w));
+		SetConsoleTitleW(w);
+	}
 #endif
+
 	/*
 	 * Select the proper prompt and display it.
 	 */
@@ -759,6 +793,14 @@ prompt()
 		putchr(':');
 	else
 	{
+#if MSDOS_COMPILER==WIN32C
+		WCHAR w[MAX_PATH*2];
+		char  a[MAX_PATH*2];
+		MultiByteToWideChar(CP_ACP, 0, p, -1, w, sizeof(w)/sizeof(*w));
+		WideCharToMultiByte(utf_mode ? CP_UTF8 : GetConsoleOutputCP(),
+		                    0, w, -1, a, sizeof(a), NULL, NULL);
+		p = a;
+#endif
 		at_enter(AT_STANDOUT);
 		putstr(p);
 		at_exit();
@@ -770,7 +812,7 @@ prompt()
  * Display the less version message.
  */
 	public void
-dispversion()
+dispversion(VOID_PARAM)
 {
 	PARG parg;
 
@@ -782,7 +824,7 @@ dispversion()
  * Return a character to complete a partial command, if possible.
  */
 	static LWCHAR
-getcc_end_command()
+getcc_end_command(VOID_PARAM)
 {
 	switch (mca)
 	{
@@ -878,10 +920,10 @@ getcc_repl(orig, repl, gr_getc, gr_ungetc)
  * Get command character.
  */
 	public int
-getcc()
+getcc(VOID_PARAM)
 {
-    /* Replace kent (keypad Enter) with a newline. */
-    return getcc_repl(kent, "\n", getccu, ungetcc);
+	/* Replace kent (keypad Enter) with a newline. */
+	return getcc_repl(kent, "\n", getccu, ungetcc);
 }
 
 /*
@@ -917,7 +959,7 @@ ungetsc(s)
  * Peek the next command character, without consuming it.
  */
 	public LWCHAR
-peekcc()
+peekcc(VOID_PARAM)
 {
 	LWCHAR c = getcc();
 	ungetcc(c);
@@ -1068,7 +1110,7 @@ forw_loop(until_hilite)
  * Accept and execute commands until a quit command.
  */
 	public void
-commands()
+commands(VOID_PARAM)
 {
 	int c;
 	int action;
@@ -1088,7 +1130,7 @@ commands()
 
 	for (;;)
 	{
-		mca = 0;
+		clear_mca();
 		cmd_accept();
 		number = 0;
 		curropt = NULL;
@@ -1270,6 +1312,22 @@ commands()
 			backward((int) number, 0, 0);
 			break;
 
+		case A_F_MOUSE:
+			/*
+			 * Forward wheel_lines lines.
+			 */
+			cmd_exec();
+			forward(wheel_lines, 0, 0);
+			break;
+
+		case A_B_MOUSE:
+			/*
+			 * Backward wheel_lines lines.
+			 */
+			cmd_exec();
+			backward(wheel_lines, 0, 0);
+			break;
+
 		case A_FF_LINE:
 			/*
 			 * Force forward N (default 1) line.
@@ -1375,7 +1433,7 @@ commands()
 				number = 0;
 				fraction = 0;
 			}
-			if (number > 100)
+			if (number > 100 || (number == 100 && fraction != 0))
 			{
 				number = 100;
 				fraction = 0;
diff --git a/compose.uni b/compose.uni
index 2a4b18025259..389814caa023 100644
--- a/compose.uni
+++ b/compose.uni
@@ -1,5 +1,4 @@
-/* Generated by "./mkutable -f2 Mn Me Cf -- unicode/UnicodeData.txt" on Tue Jul 25 09:04:35 PDT 2017 */
-	{ 0x00ad, 0x00ad }, /* Cf */
+/* Generated by "./mkutable -f2 Mn Me -- unicode/UnicodeData.txt" on Wed Feb 13 17:57:05 PST 2019 */
 	{ 0x0300, 0x036f }, /* Mn */
 	{ 0x0483, 0x0487 }, /* Mn */
 	{ 0x0488, 0x0489 }, /* Me */
@@ -8,28 +7,24 @@
 	{ 0x05c1, 0x05c2 }, /* Mn */
 	{ 0x05c4, 0x05c5 }, /* Mn */
 	{ 0x05c7, 0x05c7 }, /* Mn */
-	{ 0x0600, 0x0605 }, /* Cf */
 	{ 0x0610, 0x061a }, /* Mn */
-	{ 0x061c, 0x061c }, /* Cf */
 	{ 0x064b, 0x065f }, /* Mn */
 	{ 0x0670, 0x0670 }, /* Mn */
 	{ 0x06d6, 0x06dc }, /* Mn */
-	{ 0x06dd, 0x06dd }, /* Cf */
 	{ 0x06df, 0x06e4 }, /* Mn */
 	{ 0x06e7, 0x06e8 }, /* Mn */
 	{ 0x06ea, 0x06ed }, /* Mn */
-	{ 0x070f, 0x070f }, /* Cf */
 	{ 0x0711, 0x0711 }, /* Mn */
 	{ 0x0730, 0x074a }, /* Mn */
 	{ 0x07a6, 0x07b0 }, /* Mn */
 	{ 0x07eb, 0x07f3 }, /* Mn */
+	{ 0x07fd, 0x07fd }, /* Mn */
 	{ 0x0816, 0x0819 }, /* Mn */
 	{ 0x081b, 0x0823 }, /* Mn */
 	{ 0x0825, 0x0827 }, /* Mn */
 	{ 0x0829, 0x082d }, /* Mn */
 	{ 0x0859, 0x085b }, /* Mn */
-	{ 0x08d4, 0x08e1 }, /* Mn */
-	{ 0x08e2, 0x08e2 }, /* Cf */
+	{ 0x08d3, 0x08e1 }, /* Mn */
 	{ 0x08e3, 0x0902 }, /* Mn */
 	{ 0x093a, 0x093a }, /* Mn */
 	{ 0x093c, 0x093c }, /* Mn */
@@ -42,6 +37,7 @@
 	{ 0x09c1, 0x09c4 }, /* Mn */
 	{ 0x09cd, 0x09cd }, /* Mn */
 	{ 0x09e2, 0x09e3 }, /* Mn */
+	{ 0x09fe, 0x09fe }, /* Mn */
 	{ 0x0a01, 0x0a02 }, /* Mn */
 	{ 0x0a3c, 0x0a3c }, /* Mn */
 	{ 0x0a41, 0x0a42 }, /* Mn */
@@ -68,6 +64,7 @@
 	{ 0x0bc0, 0x0bc0 }, /* Mn */
 	{ 0x0bcd, 0x0bcd }, /* Mn */
 	{ 0x0c00, 0x0c00 }, /* Mn */
+	{ 0x0c04, 0x0c04 }, /* Mn */
 	{ 0x0c3e, 0x0c40 }, /* Mn */
 	{ 0x0c46, 0x0c48 }, /* Mn */
 	{ 0x0c4a, 0x0c4d }, /* Mn */
@@ -126,7 +123,6 @@
 	{ 0x17c9, 0x17d3 }, /* Mn */
 	{ 0x17dd, 0x17dd }, /* Mn */
 	{ 0x180b, 0x180d }, /* Mn */
-	{ 0x180e, 0x180e }, /* Cf */
 	{ 0x1885, 0x1886 }, /* Mn */
 	{ 0x18a9, 0x18a9 }, /* Mn */
 	{ 0x1920, 0x1922 }, /* Mn */
@@ -168,10 +164,6 @@
 	{ 0x1cf8, 0x1cf9 }, /* Mn */
 	{ 0x1dc0, 0x1df9 }, /* Mn */
 	{ 0x1dfb, 0x1dff }, /* Mn */
-	{ 0x200b, 0x200f }, /* Cf */
-	{ 0x202a, 0x202e }, /* Cf */
-	{ 0x2060, 0x2064 }, /* Cf */
-	{ 0x2066, 0x206f }, /* Cf */
 	{ 0x20d0, 0x20dc }, /* Mn */
 	{ 0x20dd, 0x20e0 }, /* Me */
 	{ 0x20e1, 0x20e1 }, /* Mn */
@@ -193,6 +185,7 @@
 	{ 0xa825, 0xa826 }, /* Mn */
 	{ 0xa8c4, 0xa8c5 }, /* Mn */
 	{ 0xa8e0, 0xa8f1 }, /* Mn */
+	{ 0xa8ff, 0xa8ff }, /* Mn */
 	{ 0xa926, 0xa92d }, /* Mn */
 	{ 0xa947, 0xa951 }, /* Mn */
 	{ 0xa980, 0xa982 }, /* Mn */
@@ -219,8 +212,6 @@
 	{ 0xfb1e, 0xfb1e }, /* Mn */
 	{ 0xfe00, 0xfe0f }, /* Mn */
 	{ 0xfe20, 0xfe2f }, /* Mn */
-	{ 0xfeff, 0xfeff }, /* Cf */
-	{ 0xfff9, 0xfffb }, /* Cf */
 	{ 0x101fd, 0x101fd }, /* Mn */
 	{ 0x102e0, 0x102e0 }, /* Mn */
 	{ 0x10376, 0x1037a }, /* Mn */
@@ -230,19 +221,20 @@
 	{ 0x10a38, 0x10a3a }, /* Mn */
 	{ 0x10a3f, 0x10a3f }, /* Mn */
 	{ 0x10ae5, 0x10ae6 }, /* Mn */
+	{ 0x10d24, 0x10d27 }, /* Mn */
+	{ 0x10f46, 0x10f50 }, /* Mn */
 	{ 0x11001, 0x11001 }, /* Mn */
 	{ 0x11038, 0x11046 }, /* Mn */
 	{ 0x1107f, 0x11081 }, /* Mn */
 	{ 0x110b3, 0x110b6 }, /* Mn */
 	{ 0x110b9, 0x110ba }, /* Mn */
-	{ 0x110bd, 0x110bd }, /* Cf */
 	{ 0x11100, 0x11102 }, /* Mn */
 	{ 0x11127, 0x1112b }, /* Mn */
 	{ 0x1112d, 0x11134 }, /* Mn */
 	{ 0x11173, 0x11173 }, /* Mn */
 	{ 0x11180, 0x11181 }, /* Mn */
 	{ 0x111b6, 0x111be }, /* Mn */
-	{ 0x111ca, 0x111cc }, /* Mn */
+	{ 0x111c9, 0x111cc }, /* Mn */
 	{ 0x1122f, 0x11231 }, /* Mn */
 	{ 0x11234, 0x11234 }, /* Mn */
 	{ 0x11236, 0x11237 }, /* Mn */
@@ -250,13 +242,14 @@
 	{ 0x112df, 0x112df }, /* Mn */
 	{ 0x112e3, 0x112ea }, /* Mn */
 	{ 0x11300, 0x11301 }, /* Mn */
-	{ 0x1133c, 0x1133c }, /* Mn */
+	{ 0x1133b, 0x1133c }, /* Mn */
 	{ 0x11340, 0x11340 }, /* Mn */
 	{ 0x11366, 0x1136c }, /* Mn */
 	{ 0x11370, 0x11374 }, /* Mn */
 	{ 0x11438, 0x1143f }, /* Mn */
 	{ 0x11442, 0x11444 }, /* Mn */
 	{ 0x11446, 0x11446 }, /* Mn */
+	{ 0x1145e, 0x1145e }, /* Mn */
 	{ 0x114b3, 0x114b8 }, /* Mn */
 	{ 0x114ba, 0x114ba }, /* Mn */
 	{ 0x114bf, 0x114c0 }, /* Mn */
@@ -275,8 +268,9 @@
 	{ 0x1171d, 0x1171f }, /* Mn */
 	{ 0x11722, 0x11725 }, /* Mn */
 	{ 0x11727, 0x1172b }, /* Mn */
-	{ 0x11a01, 0x11a06 }, /* Mn */
-	{ 0x11a09, 0x11a0a }, /* Mn */
+	{ 0x1182f, 0x11837 }, /* Mn */
+	{ 0x11839, 0x1183a }, /* Mn */
+	{ 0x11a01, 0x11a0a }, /* Mn */
 	{ 0x11a33, 0x11a38 }, /* Mn */
 	{ 0x11a3b, 0x11a3e }, /* Mn */
 	{ 0x11a47, 0x11a47 }, /* Mn */
@@ -296,13 +290,15 @@
 	{ 0x11d3c, 0x11d3d }, /* Mn */
 	{ 0x11d3f, 0x11d45 }, /* Mn */
 	{ 0x11d47, 0x11d47 }, /* Mn */
+	{ 0x11d90, 0x11d91 }, /* Mn */
+	{ 0x11d95, 0x11d95 }, /* Mn */
+	{ 0x11d97, 0x11d97 }, /* Mn */
+	{ 0x11ef3, 0x11ef4 }, /* Mn */
 	{ 0x16af0, 0x16af4 }, /* Mn */
 	{ 0x16b30, 0x16b36 }, /* Mn */
 	{ 0x16f8f, 0x16f92 }, /* Mn */
 	{ 0x1bc9d, 0x1bc9e }, /* Mn */
-	{ 0x1bca0, 0x1bca3 }, /* Cf */
 	{ 0x1d167, 0x1d169 }, /* Mn */
-	{ 0x1d173, 0x1d17a }, /* Cf */
 	{ 0x1d17b, 0x1d182 }, /* Mn */
 	{ 0x1d185, 0x1d18b }, /* Mn */
 	{ 0x1d1aa, 0x1d1ad }, /* Mn */
@@ -320,6 +316,4 @@
 	{ 0x1e026, 0x1e02a }, /* Mn */
 	{ 0x1e8d0, 0x1e8d6 }, /* Mn */
 	{ 0x1e944, 0x1e94a }, /* Mn */
-	{ 0xe0001, 0xe0001 }, /* Cf */
-	{ 0xe0020, 0xe007f }, /* Cf */
 	{ 0xe0100, 0xe01ef }, /* Mn */
diff --git a/configure b/configure
index 10a0305e7282..0ce6db15e3a1 100755
--- a/configure
+++ b/configure
@@ -1307,7 +1307,7 @@ Optional Packages:
   --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no)
   --with-secure           Compile in secure mode
   --with-no-float         Do not use floating point
-  --with-regex=LIB        select regular expression library (LIB is one of auto,none,gnu,pcre,posix,regcmp,re_comp,regcomp,regcomp-local) [auto]
+  --with-regex=LIB        select regular expression library (LIB is one of auto,none,gnu,pcre,pcre2,posix,regcmp,re_comp,regcomp,regcomp-local) [auto]
   --with-editor=PROGRAM   use PROGRAM as the default editor [vi]
 
 Some influential environment variables:
@@ -4611,6 +4611,7 @@ fi
 
 
 
+
 # Checks for identifiers.
 ac_fn_c_check_type "$LINENO" "off_t" "ac_cv_type_off_t" "$ac_includes_default"
 if test "x$ac_cv_type_off_t" = xyes; then :
@@ -4771,7 +4772,7 @@ cat >>confdefs.h <<_ACEOF
 _ACEOF
 
 
-for ac_func in fsync popen _setjmp sigprocmask sigsetmask snprintf stat system fchmod
+for ac_func in fsync popen _setjmp sigprocmask sigsetmask snprintf stat system fchmod realpath
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
@@ -5312,6 +5313,52 @@ fi
 fi
 
 if test $have_regex = no; then
+if test $WANT_REGEX = auto -o $WANT_REGEX = pcre2; then
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for pcre2_compile_8 in -lpcre2-8" >&5
+$as_echo_n "checking for pcre2_compile_8 in -lpcre2-8... " >&6; }
+if ${ac_cv_lib_pcre2_8_pcre2_compile_8+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lpcre2-8  $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char pcre2_compile_8 ();
+int
+main ()
+{
+return pcre2_compile_8 ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_lib_pcre2_8_pcre2_compile_8=yes
+else
+  ac_cv_lib_pcre2_8_pcre2_compile_8=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_pcre2_8_pcre2_compile_8" >&5
+$as_echo "$ac_cv_lib_pcre2_8_pcre2_compile_8" >&6; }
+if test "x$ac_cv_lib_pcre2_8_pcre2_compile_8" = xyes; then :
+  $as_echo "#define HAVE_PCRE2 1" >>confdefs.h
+ LIBS="$LIBS -lpcre2-8" have_regex=yes; supported_regex="$supported_regex pcre2"
+fi
+
+fi
+fi
+
+if test $have_regex = no; then
 if test $WANT_REGEX = auto -o $WANT_REGEX = pcre; then
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for pcre_compile in -lpcre" >&5
 $as_echo_n "checking for pcre_compile in -lpcre... " >&6; }
diff --git a/configure.ac b/configure.ac
index 3616ef035f71..7a693982ccf9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -183,6 +183,8 @@ AH_TEMPLATE([HAVE_POSIX_REGCOMP],
 	[POSIX regcomp() and regex.h])
 AH_TEMPLATE([HAVE_PCRE],
 	[PCRE (Perl-compatible regular expression) library])
+AH_TEMPLATE([HAVE_PCRE2],
+	[PCRE2 (Perl-compatible regular expression) library])
 AH_TEMPLATE([HAVE_RE_COMP],
 	[BSD re_comp()])
 AH_TEMPLATE([HAVE_REGCMP],
@@ -258,7 +260,7 @@ AC_TRY_COMPILE([], [int f(int a) { return a; }],
 
 # Checks for library functions.
 AC_TYPE_SIGNAL
-AC_CHECK_FUNCS([fsync popen _setjmp sigprocmask sigsetmask snprintf stat system fchmod])
+AC_CHECK_FUNCS([fsync popen _setjmp sigprocmask sigsetmask snprintf stat system fchmod realpath])
 
 # AC_CHECK_FUNCS may not work for inline functions, so test these separately.
 AC_MSG_CHECKING(for memcpy)
@@ -393,7 +395,7 @@ supported_regex=""
 # Select a regular expression library.
 WANT_REGEX=auto
 AC_ARG_WITH(regex,
-  [  --with-regex=LIB        select regular expression library (LIB is one of auto,none,gnu,pcre,posix,regcmp,re_comp,regcomp,regcomp-local) [[auto]]],
+  [  --with-regex=LIB        select regular expression library (LIB is one of auto,none,gnu,pcre,pcre2,posix,regcmp,re_comp,regcomp,regcomp-local) [[auto]]],
   WANT_REGEX="$withval")
 
 if test $have_regex = no; then
@@ -432,6 +434,13 @@ fi
 fi
 
 if test $have_regex = no; then
+if test $WANT_REGEX = auto -o $WANT_REGEX = pcre2; then
+AC_CHECK_LIB(pcre2-8, pcre2_compile_8, 
+[AC_DEFINE(HAVE_PCRE2) LIBS="$LIBS -lpcre2-8" have_regex=yes; supported_regex="$supported_regex pcre2"], [])
+fi
+fi
+
+if test $have_regex = no; then
 if test $WANT_REGEX = auto -o $WANT_REGEX = pcre; then
 AC_CHECK_LIB(pcre, pcre_compile, 
 [AC_DEFINE(HAVE_PCRE) LIBS="$LIBS -lpcre" have_regex=yes; supported_regex="$supported_regex pcre"], [])
@@ -575,7 +584,7 @@ AH_TOP([
 #define	PIPEC		(!SECURE)
 
 /*
- * LOGFILE is 1 if you wish to allow the -l option (to create log files).
+ * LOGFILE is 1 if you wish to allow the -o option (to create log files).
  */
 #define	LOGFILE		(!SECURE)
 
diff --git a/cvt.c b/cvt.c
index 3a779490439d..e635655dd1be 100644
--- a/cvt.c
+++ b/cvt.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
diff --git a/decode.c b/decode.c
index 80f47f99d155..74bbc4fdaf3f 100644
--- a/decode.c
+++ b/decode.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -35,6 +35,9 @@
 
 extern int erase_char, erase2_char, kill_char;
 extern int secure;
+extern int mousecap;
+extern int screen_trashed;
+extern int sc_height;
 
 #define SK(k) \
 	SK_SPECIAL_KEY, (k), 6, 1, 1, 1
@@ -65,6 +68,8 @@ static unsigned char cmdtable[] =
 	CONTROL('D'),0,			A_F_SCROLL,
 	'u',0,				A_B_SCROLL,
 	CONTROL('U'),0,			A_B_SCROLL,
+	ESC,'[','M',0,			A_X11MOUSE_IN,
+	ESC,'[','<',0,			A_X116MOUSE_IN,
 	' ',0,				A_F_SCREEN,
 	'f',0,				A_F_SCREEN,
 	CONTROL('F'),0,			A_F_SCREEN,
@@ -310,7 +315,7 @@ expand_cmd_table(tlist)
  * Expand special key abbreviations in all command tables.
  */
 	public void
-expand_cmd_tables()
+expand_cmd_tables(VOID_PARAM)
 {
 	expand_cmd_table(list_fcmd_tables);
 	expand_cmd_table(list_ecmd_tables);
@@ -323,7 +328,7 @@ expand_cmd_tables()
  * Initialize the command lists.
  */
 	public void
-init_cmds()
+init_cmds(VOID_PARAM)
 {
 	/*
 	 * Add the default command tables.
@@ -416,6 +421,116 @@ add_var_table(tlist, buf, len)
 }
 
 /*
+ * Return action for a mouse wheel down event.
+ */
+	static int
+mouse_wheel_down(VOID_PARAM)
+{
+	return ((mousecap == OPT_ONPLUS) ? A_B_MOUSE : A_F_MOUSE);
+}
+
+/*
+ * Return action for a mouse wheel up event.
+ */
+	static int
+mouse_wheel_up(VOID_PARAM)
+{
+	return ((mousecap == OPT_ONPLUS) ? A_F_MOUSE : A_B_MOUSE);
+}
+
+/*
+ * Return action for a mouse button release event.
+ */
+	static int
+mouse_button_rel(x, y)
+	int x;
+	int y;
+{
+	/*
+	 * {{ It would be better to return an action and then do this 
+	 *    in commands() but it's nontrivial to pass y to it. }}
+	 */
+	if (y < sc_height-1)
+	{
+		setmark('#', y);
+		screen_trashed = 1;
+	}
+	return (A_NOACTION);
+}
+
+/*
+ * Read a decimal integer. Return the integer and set *pterm to the terminating char.
+ */
+	static int
+getcc_int(pterm)
+	char* pterm;
+{
+	int num = 0;
+	int digits = 0;
+	for (;;)
+	{
+		char ch = getcc();
+		if (ch < '0' || ch > '9')
+		{
+			if (pterm != NULL) *pterm = ch;
+			if (digits == 0)
+				return (-1);
+			return (num);
+		}
+		num = (10 * num) + (ch - '0');
+		++digits;
+	}
+}
+
+/*
+ * Read suffix of mouse input and return the action to take.
+ * The prefix ("\e[M") has already been read.
+ */
+	static int
+x11mouse_action(VOID_PARAM)
+{
+	int b = getcc() - X11MOUSE_OFFSET;
+	int x = getcc() - X11MOUSE_OFFSET-1;
+	int y = getcc() - X11MOUSE_OFFSET-1;
+	switch (b) {
+	default:
+		return (A_NOACTION);
+	case X11MOUSE_WHEEL_DOWN:
+		return mouse_wheel_down();
+	case X11MOUSE_WHEEL_UP:
+		return mouse_wheel_up();
+	case X11MOUSE_BUTTON_REL:
+		return mouse_button_rel(x, y);
+	}
+}
+
+/*
+ * Read suffix of mouse input and return the action to take.
+ * The prefix ("\e[<") has already been read.
+ */
+	static int
+x116mouse_action(VOID_PARAM)
+{
+	char ch;
+	int x, y;
+	int b = getcc_int(&ch);
+	if (b < 0 || ch != ';') return (A_NOACTION);
+	x = getcc_int(&ch) - 1;
+	if (x < 0 || ch != ';') return (A_NOACTION);
+	y = getcc_int(&ch) - 1;
+	if (y < 0) return (A_NOACTION);
+	switch (b) {
+	case X11MOUSE_WHEEL_DOWN:
+		return mouse_wheel_down();
+	case X11MOUSE_WHEEL_UP:
+		return mouse_wheel_up();
+	default:
+		if (ch != 'm') return (A_NOACTION);
+		return mouse_button_rel(x, y);
+	}
+}
+
+/*
  * Search a single command table for the command string in cmd.
  */
 	static int
@@ -464,6 +579,10 @@ cmd_search(cmd, table, endtable, sp)
 					*sp = ++p;
 					a &= ~A_EXTRA;
 				}
+				if (a == A_X11MOUSE_IN)
+					a = x11mouse_action();
+				else if (a == A_X116MOUSE_IN)
+					a = x116mouse_action();
 				return (a);
 			}
 		} else if (*q == '\0')
@@ -579,6 +698,16 @@ lgetenv(var)
 	return (NULL);
 }
 
+/*
+ * Is a string null or empty? 
+ */
+	public int
+isnullenv(s)
+	char* s;
+{
+	return (s == NULL || *s == '\0');
+}
+
 #if USERFILE
 /*
  * Get an "integer" from a lesskey file.
@@ -791,7 +920,13 @@ editchar(c, flags)
 	if (c == erase_char || c == erase2_char)
 		return (EC_BACKSPACE);
 	if (c == kill_char)
+	{
+#if MSDOS_COMPILER==WIN32C
+		if (!win32_kbhit())
+#endif
+
 		return (EC_LINEKILL);
+	}
 		
 	/*
 	 * Collect characters in a buffer.
diff --git a/defines.ds b/defines.ds
index 80a2d7b1b659..b952232b8de5 100644
--- a/defines.ds
+++ b/defines.ds
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -93,7 +93,7 @@
 #endif
 
 /*
- * LOGFILE is 1 if you wish to allow the -l option (to create log files).
+ * LOGFILE is 1 if you wish to allow the -o option (to create log files).
  */
 #define	LOGFILE		(!SECURE)
 
diff --git a/defines.h.in b/defines.h.in
index 874c15057a2b..36822bc41148 100644
--- a/defines.h.in
+++ b/defines.h.in
@@ -83,7 +83,7 @@
 #define	PIPEC		(!SECURE)
 
 /*
- * LOGFILE is 1 if you wish to allow the -l option (to create log files).
+ * LOGFILE is 1 if you wish to allow the -o option (to create log files).
  */
 #define	LOGFILE		(!SECURE)
 
@@ -263,12 +263,18 @@
 /* PCRE (Perl-compatible regular expression) library */
 #undef HAVE_PCRE
 
+/* PCRE2 (Perl-compatible regular expression) library */
+#undef HAVE_PCRE2
+
 /* Define to 1 if you have the `popen' function. */
 #undef HAVE_POPEN
 
 /* POSIX regcomp() and regex.h */
 #undef HAVE_POSIX_REGCOMP
 
+/* Define to 1 if you have the `realpath' function. */
+#undef HAVE_REALPATH
+
 /* System V regcmp() */
 #undef HAVE_REGCMP
 
diff --git a/defines.o2 b/defines.o2
index 4dba1423c080..1490cdcbb039 100644
--- a/defines.o2
+++ b/defines.o2
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -86,7 +86,7 @@
 #define	PIPEC		(!SECURE)
 
 /*
- * LOGFILE is 1 if you wish to allow the -l option (to create log files).
+ * LOGFILE is 1 if you wish to allow the -o option (to create log files).
  */
 #define	LOGFILE		(!SECURE)
 
diff --git a/defines.o9 b/defines.o9
index 99983d726a97..fb980ac2c31f 100644
--- a/defines.o9
+++ b/defines.o9
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -85,7 +85,7 @@
 #define	PIPEC		(!SECURE)
 
 /*
- * LOGFILE is 1 if you wish to allow the -l option (to create log files).
+ * LOGFILE is 1 if you wish to allow the -o option (to create log files).
  */
 #define	LOGFILE		(!SECURE)
 
diff --git a/defines.wn b/defines.wn
index 98ca9905862a..42354022cd6d 100644
--- a/defines.wn
+++ b/defines.wn
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -86,7 +86,7 @@
 #define	PIPEC		1
 
 /*
- * LOGFILE is 1 if you wish to allow the -l option (to create log files).
+ * LOGFILE is 1 if you wish to allow the -o option (to create log files).
  */
 #define	LOGFILE		(!SECURE)
 
@@ -172,7 +172,7 @@
 /*
  * Sizes of various buffers.
  */
-#if 0 /* old sizes for small memory machines
+#if 0 /* old sizes for small memory machines */
 #define	CMDBUF_SIZE	512	/* Buffer for multichar commands */
 #define	UNGOT_SIZE	100	/* Max chars to unget() */
 #define	LINEBUF_SIZE	1024	/* Max size of line in input file */
@@ -216,9 +216,26 @@
 /* #undef HAVE_POSIX_REGCOMP */
 /* #undef HAVE_RE_COMP */
 /* #undef HAVE_REGCMP */
+#ifdef MINGW
+    #ifdef USE_POSIX_REGCOMP
+	#define HAVE_POSIX_REGCOMP 1
+    #else
+	#ifdef USE_GNU_REGEX
+	    #define HAVE_GNU_REGEX  1
+        #else
+            #ifdef USE_REGEXP_C
+		#define HAVE_V8_REGCOMP 1
+		#define HAVE_REGEXEC2   1
+            #else
+                #define NO_REGEX 1
+	    #endif
+	#endif
+    #endif
+#else
 #define HAVE_V8_REGCOMP 1
 /* #undef NO_REGEX */
 #define HAVE_REGEXEC2 1
+#endif
 
 /* Define HAVE_VOID if your compiler supports the "void" type. */
 #define HAVE_VOID 1
@@ -239,7 +256,11 @@
 /* Define MUST_DEFINE_ERRNO if you have errno but it is not define 
  * in errno.h */
 #define HAVE_ERRNO 1
+#ifdef MINGW
+#define MUST_DEFINE_ERRNO 0
+#else
 #define MUST_DEFINE_ERRNO 1
+#endif
 
 /* Define HAVE_SYS_ERRLIST if you have the sys_errlist[] variable */
 #define HAVE_SYS_ERRLIST 1
@@ -339,19 +360,28 @@
 #define HAVE_TIME_H 1
 
 /* Define if you have the <unistd.h> header file.  */
+#ifdef MINGW
+#define HAVE_UNISTD_H 1
+#else
 #define HAVE_UNISTD_H 0
+#endif
 
 /* Define if you have the <values.h> header file.  */
 #ifdef _MSC_VER
 #define HAVE_VALUES_H 0
 #else
+#ifdef MINGW
+#define HAVE_VALUES_H 0
+#else
 #define HAVE_VALUES_H 1
 #endif
+#endif
 
 #define	popen	_popen
-#define	pclose	_pclose
 #if !defined(_MSC_VER) || (_MSC_VER < 1900) 
 #define snprintf	_snprintf
 #endif
 
+#ifndef MINGW
 #pragma warning(disable:4996)
+#endif
diff --git a/edit.c b/edit.c
index 7dc80bbd6453..82a79b134c3e 100644
--- a/edit.c
+++ b/edit.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -171,7 +171,7 @@ close_pipe(FILE *pipefd)
  * Close the current input file.
  */
 	static void
-close_file()
+close_file(VOID_PARAM)
 {
 	struct scrpos scrpos;
 	int chflags;
@@ -486,7 +486,12 @@ edit_ifile(ifile)
 		clr_hilite();
 #endif
 		if (strcmp(filename, FAKE_HELPFILE) && strcmp(filename, FAKE_EMPTYFILE))
-			cmd_addhist(ml_examine, filename, 1);
+		{
+			char *qfilename = shell_quote(filename);
+			cmd_addhist(ml_examine, qfilename, 1);
+			free(qfilename);
+		}
+
 		if (no_display && errmsgs > 0)
 		{
 			/*
@@ -570,8 +575,10 @@ edit_list(filelist)
  * Edit the first file in the command line (ifile) list.
  */
 	public int
-edit_first()
+edit_first(VOID_PARAM)
 {
+	if (nifile() == 0)
+		return (edit_stdin());
 	curr_ifile = NULL_IFILE;
 	return (edit_next(1));
 }
@@ -580,7 +587,7 @@ edit_first()
  * Edit the last file in the command line (ifile) list.
  */
 	public int
-edit_last()
+edit_last(VOID_PARAM)
 {
 	curr_ifile = NULL_IFILE;
 	return (edit_prev(1));
@@ -687,7 +694,7 @@ edit_index(n)
 }
 
 	public IFILE
-save_curr_ifile()
+save_curr_ifile(VOID_PARAM)
 {
 	if (curr_ifile != NULL_IFILE)
 		hold_ifile(curr_ifile, 1);
@@ -740,7 +747,7 @@ reedit_ifile(save_ifile)
 }
 
 	public void
-reopen_curr_ifile()
+reopen_curr_ifile(VOID_PARAM)
 {
 	IFILE save_ifile = save_curr_ifile();
 	close_file();
@@ -751,7 +758,7 @@ reopen_curr_ifile()
  * Edit standard input.
  */
 	public int
-edit_stdin()
+edit_stdin(VOID_PARAM)
 {
 	if (isatty(fd0))
 	{
@@ -766,7 +773,7 @@ edit_stdin()
  * Used if standard output is not a tty.
  */
 	public void
-cat_file()
+cat_file(VOID_PARAM)
 {
 	int c;
 
diff --git a/filename.c b/filename.c
index 983a02b0e062..7c3ccd2e97a5 100644
--- a/filename.c
+++ b/filename.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -98,7 +98,7 @@ shell_unquote(str)
  * Get the shell's escape character.
  */
 	public char *
-get_meta_escape()
+get_meta_escape(VOID_PARAM)
 {
 	char *s;
 
@@ -112,7 +112,7 @@ get_meta_escape()
  * Get the characters which the shell considers to be "metacharacters".
  */
 	static char *
-metachars()
+metachars(VOID_PARAM)
 {
 	static char *mchars = NULL;
 
@@ -561,8 +561,6 @@ readfd(fd)
 
 #if HAVE_POPEN
 
-FILE *popen();
-
 /*
  * Execute a shell command.
  * Return a pointer to a pipe connected to the shell command's standard output.
@@ -577,7 +575,7 @@ shellcmd(cmd)
 	char *shell;
 
 	shell = lgetenv("SHELL");
-	if (shell != NULL && *shell != '\0')
+	if (!isnullenv(shell))
 	{
 		char *scmd;
 		char *esccmd;
@@ -754,7 +752,7 @@ lglob(filename)
 		return (filename);
 	}
 	lessecho = lgetenv("LESSECHO");
-	if (lessecho == NULL || *lessecho == '\0')
+	if (isnullenv(lessecho))
 		lessecho = "lessecho";
 	/*
 	 * Invoke lessecho, and read its output (a globbed list of filenames).
@@ -781,7 +779,7 @@ lglob(filename)
 	if (*gfilename == '\0')
 	{
 		free(gfilename);
-		return (save(filename));
+		return (filename);
 	}
 }
 #else
@@ -797,6 +795,21 @@ lglob(filename)
 }
 
 /*
+ * @@@
+ */
+	public char *
+lrealpath(path)
+	char *path;
+{
+#if HAVE_REALPATH
+	char rpath[PATH_MAX];
+	if (realpath(path, rpath) != NULL)
+		return (save(rpath));
+#endif
+	return (save(path));
+}
+
+/*
  * Return number of %s escapes in a string.
  * Return a large number if there are any other % escapes besides %s.
  */
@@ -1080,7 +1093,7 @@ filesize(f)
  * 
  */
 	public char *
-shell_coption()
+shell_coption(VOID_PARAM)
 {
 	return ("-c");
 }
diff --git a/fmt.uni b/fmt.uni
index a0bad7784506..ff71d294c955 100644
--- a/fmt.uni
+++ b/fmt.uni
@@ -1,4 +1,4 @@
-/* Generated by "./mkutable -f2 Cf -- unicode/UnicodeData.txt" on Sun Nov 12 16:13:49 PST 2017 */
+/* Generated by "./mkutable -f2 Cf -- unicode/UnicodeData.txt" on Wed Feb 13 17:57:05 PST 2019 */
 	{ 0x00ad, 0x00ad }, /* Cf */
 	{ 0x0600, 0x0605 }, /* Cf */
 	{ 0x061c, 0x061c }, /* Cf */
@@ -13,6 +13,7 @@
 	{ 0xfeff, 0xfeff }, /* Cf */
 	{ 0xfff9, 0xfffb }, /* Cf */
 	{ 0x110bd, 0x110bd }, /* Cf */
+	{ 0x110cd, 0x110cd }, /* Cf */
 	{ 0x1bca0, 0x1bca3 }, /* Cf */
 	{ 0x1d173, 0x1d17a }, /* Cf */
 	{ 0xe0001, 0xe0001 }, /* Cf */
diff --git a/forwback.c b/forwback.c
index 680fa251b12e..1e0397c9a765 100644
--- a/forwback.c
+++ b/forwback.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -46,7 +46,7 @@ extern char *tagoption;
  * Sound the bell to indicate user is trying to move past end of file.
  */
 	static void
-eof_bell()
+eof_bell(VOID_PARAM)
 {
 	if (quiet == NOT_QUIET)
 		bell();
@@ -58,7 +58,7 @@ eof_bell()
  * Check to see if the end of file is currently displayed.
  */
 	public int
-eof_displayed()
+eof_displayed(VOID_PARAM)
 {
 	POSITION pos;
 
@@ -85,7 +85,7 @@ eof_displayed()
  * Check to see if the entire file is currently displayed.
  */
 	public int
-entire_file_displayed()
+entire_file_displayed(VOID_PARAM)
 {
 	POSITION pos;
 
@@ -105,7 +105,7 @@ entire_file_displayed()
  * for the first time.
  */
 	public void
-squish_check()
+squish_check(VOID_PARAM)
 {
 	if (!squished)
 		return;
@@ -434,7 +434,7 @@ backward(n, force, only_last)
  * top_scroll, as well as back_scroll.
  */
 	public int
-get_back_scroll()
+get_back_scroll(VOID_PARAM)
 {
 	if (no_back_scroll)
 		return (0);
@@ -446,19 +446,18 @@ get_back_scroll()
 }
 
 /*
- * Return number of displayable lines in the file.
- * Stop counting at screen height + 1.
+ * Will the entire file fit on one screen?
  */
 	public int
-get_line_count()
+get_one_screen(VOID_PARAM)
 {
 	int nlines;
 	POSITION pos = ch_zero();
 
-	for (nlines = 0;  nlines <= sc_height;  nlines++)
+	for (nlines = 0;  nlines < sc_height;  nlines++)
 	{
 		pos = forw_line(pos);
 		if (pos == NULL_POSITION) break;
 	}
-	return nlines;
+	return (nlines < sc_height);
 }
diff --git a/funcs.h b/funcs.h
index d70c359df5a3..9686df1d7851 100644
--- a/funcs.h
+++ b/funcs.h
@@ -7,6 +7,8 @@ public void raw_mode LESSPARAMS ((int on));
 public void scrsize LESSPARAMS ((VOID_PARAM));
 public char * special_key_str LESSPARAMS ((int key));
 public void get_term LESSPARAMS ((VOID_PARAM));
+public void init_mouse LESSPARAMS ((VOID_PARAM));
+public void deinit_mouse LESSPARAMS ((VOID_PARAM));
 public void init LESSPARAMS ((VOID_PARAM));
 public void deinit LESSPARAMS ((VOID_PARAM));
 public void home LESSPARAMS ((VOID_PARAM));
@@ -29,7 +31,8 @@ public int is_at_equiv LESSPARAMS ((int attr1, int attr2));
 public int apply_at_specials LESSPARAMS ((int attr));
 public void backspace LESSPARAMS ((VOID_PARAM));
 public void putbs LESSPARAMS ((VOID_PARAM));
-public char WIN32getch LESSPARAMS ((int tty));
+public int win32_kbhit LESSPARAMS ((VOID_PARAM));
+public char WIN32getch LESSPARAMS ((VOID_PARAM));
 public void WIN32setcolors LESSPARAMS ((int fg, int bg));
 public void WIN32textout LESSPARAMS ((char *text, int len));
 public void match_brac LESSPARAMS ((int obrac, int cbrac, int forwdir, int n));
@@ -98,6 +101,7 @@ public void add_ecmd_table LESSPARAMS ((char *buf, int len));
 public int fcmd_decode LESSPARAMS ((char *cmd, char **sp));
 public int ecmd_decode LESSPARAMS ((char *cmd, char **sp));
 public char * lgetenv LESSPARAMS ((char *var));
+public int isnullenv LESSPARAMS ((char* s));
 public int lesskey LESSPARAMS ((char *filename, int sysvar));
 public void add_hometable LESSPARAMS ((char *envname, char *def_filename, int sysvar));
 public int editchar LESSPARAMS ((int c, int flags));
@@ -127,6 +131,7 @@ public char * fexpand LESSPARAMS ((char *s));
 public char * fcomplete LESSPARAMS ((char *s));
 public int bin_file LESSPARAMS ((int f));
 public char * lglob LESSPARAMS ((char *filename));
+public char * lrealpath LESSPARAMS ((char *path));
 public char * open_altfile LESSPARAMS ((char *filename, int *pf, void **pfd));
 public void close_altfile LESSPARAMS ((char *altfilename, char *filename));
 public int is_dir LESSPARAMS ((char *filename));
@@ -142,7 +147,7 @@ public void back LESSPARAMS ((int n, POSITION pos, int force, int only_last));
 public void forward LESSPARAMS ((int n, int force, int only_last));
 public void backward LESSPARAMS ((int n, int force, int only_last));
 public int get_back_scroll LESSPARAMS ((VOID_PARAM));
-public int get_line_count LESSPARAMS ((VOID_PARAM));
+public int get_one_screen LESSPARAMS ((VOID_PARAM));
 public void del_ifile LESSPARAMS ((IFILE h));
 public IFILE next_ifile LESSPARAMS ((IFILE h));
 public IFILE prev_ifile LESSPARAMS ((IFILE h));
@@ -208,6 +213,9 @@ public void gomark LESSPARAMS ((int c));
 public POSITION markpos LESSPARAMS ((int c));
 public char posmark LESSPARAMS ((POSITION pos));
 public void unmark LESSPARAMS ((IFILE ifile));
+public void mark_check_ifile LESSPARAMS ((IFILE ifile));
+public void save_marks LESSPARAMS ((FILE *fout, char *hdr));
+public void restore_mark LESSPARAMS ((char *line));
 public void opt_o LESSPARAMS ((int type, char *s));
 public void opt__O LESSPARAMS ((int type, char *s));
 public void opt_j LESSPARAMS ((int type, char *s));
@@ -227,6 +235,8 @@ public void opt_x LESSPARAMS ((int type, char *s));
 public void opt_quote LESSPARAMS ((int type, char *s));
 public void opt_rscroll LESSPARAMS ((int type, char *s));
 public void opt_query LESSPARAMS ((int type, char *s));
+public void opt_mousecap LESSPARAMS ((int type, char *s));
+public void opt_wheel_lines LESSPARAMS ((int type, char *s));
 public int get_swindow LESSPARAMS ((VOID_PARAM));
 public char * propt LESSPARAMS ((int c));
 public void scan_option LESSPARAMS ((char *s));
@@ -261,6 +271,7 @@ public void uncompile_pattern LESSPARAMS ((PATTERN_TYPE *pattern));
 public int valid_pattern LESSPARAMS ((char *pattern));
 public int is_null_pattern LESSPARAMS ((PATTERN_TYPE pattern));
 public int match_pattern LESSPARAMS ((PATTERN_TYPE pattern, char *tpattern, char *line, int line_len, char **sp, char **ep, int notbol, int search_type));
+public char * pattern_lib_name LESSPARAMS ((VOID_PARAM));
 public POSITION position LESSPARAMS ((int sindex));
 public void add_forw_pos LESSPARAMS ((POSITION pos));
 public void add_back_pos LESSPARAMS ((POSITION pos));
@@ -307,4 +318,5 @@ public int curr_tag LESSPARAMS ((VOID_PARAM));
 public int edit_tagfile LESSPARAMS ((VOID_PARAM));
 public void open_getchr LESSPARAMS ((VOID_PARAM));
 public void close_getchr LESSPARAMS ((VOID_PARAM));
+public int default_wheel_lines LESSPARAMS ((VOID_PARAM));
 public int getchr LESSPARAMS ((VOID_PARAM));
diff --git a/help.c b/help.c
index efa236af89d9..f9c2dd95d0ba 100644
--- a/help.c
+++ b/help.c
@@ -1,4 +1,4 @@
-/* This file was generated by mkhelp.pl from less.hlp at 22:56 on 2017/12/5 */
+/* This file was generated by mkhelp.pl from less.hlp at 18:12 on 2019/6/11 */
 #include "less.h"
 constant char helpdata[] = {
 '\n',
@@ -47,7 +47,7 @@ constant char helpdata[] = {
 ' ',' ','E','S','C','-','u',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','U','n','d','o',' ','(','t','o','g','g','l','e',')',' ','s','e','a','r','c','h',' ','h','i','g','h','l','i','g','h','t','i','n','g','.','\n',
 ' ',' ','&','_','\b','p','_','\b','a','_','\b','t','_','\b','t','_','\b','e','_','\b','r','_','\b','n',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','*',' ',' ','D','i','s','p','l','a','y',' ','o','n','l','y',' ','m','a','t','c','h','i','n','g',' ','l','i','n','e','s','\n',
 ' ',' ',' ',' ',' ',' ',' ',' ','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','\n',
-' ',' ',' ',' ',' ',' ',' ',' ','A',' ','s','e','a','r','c','h',' ','p','a','t','t','e','r','n',' ','m','a','y',' ','b','e',' ','p','r','e','c','e','d','e','d',' ','b','y',' ','o','n','e',' ','o','r',' ','m','o','r','e',' ','o','f',':','\n',
+' ',' ',' ',' ',' ',' ',' ',' ','A',' ','s','e','a','r','c','h',' ','p','a','t','t','e','r','n',' ','m','a','y',' ','b','e','g','i','n',' ','w','i','t','h',' ','o','n','e',' ','o','r',' ','m','o','r','e',' ','o','f',':','\n',
 ' ',' ',' ',' ',' ',' ',' ',' ','^','N',' ','o','r',' ','!',' ',' ','S','e','a','r','c','h',' ','f','o','r',' ','N','O','N','-','m','a','t','c','h','i','n','g',' ','l','i','n','e','s','.','\n',
 ' ',' ',' ',' ',' ',' ',' ',' ','^','E',' ','o','r',' ','*',' ',' ','S','e','a','r','c','h',' ','m','u','l','t','i','p','l','e',' ','f','i','l','e','s',' ','(','p','a','s','s',' ','t','h','r','u',' ','E','N','D',' ','O','F',' ','F','I','L','E',')','.','\n',
 ' ',' ',' ',' ',' ',' ',' ',' ','^','F',' ','o','r',' ','@',' ',' ','S','t','a','r','t',' ','s','e','a','r','c','h',' ','a','t',' ','F','I','R','S','T',' ','f','i','l','e',' ','(','f','o','r',' ','/',')',' ','o','r',' ','l','a','s','t',' ','f','i','l','e',' ','(','f','o','r',' ','?',')','.','\n',
@@ -156,7 +156,7 @@ constant char helpdata[] = {
 ' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','D','i','s','p','l','a','y',' ','a',' ','s','t','a','t','u','s',' ','c','o','l','u','m','n',' ','a','t',' ','l','e','f','t',' ','e','d','g','e',' ','o','f',' ','s','c','r','e','e','n','.','\n',
 ' ',' ','-','k',' ','[','_','\b','f','_','\b','i','_','\b','l','_','\b','e',']',' ',' ','.',' ',' ','-','-','l','e','s','s','k','e','y','-','f','i','l','e','=','[','_','\b','f','_','\b','i','_','\b','l','_','\b','e',']','\n',
 ' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','U','s','e',' ','a',' ','l','e','s','s','k','e','y',' ','f','i','l','e','.','\n',
-' ',' ','-','K',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','-','-','q','u','i','t','-','o','n','-','i','n','t','r','\n',
+' ',' ','-','K',' ',' ','.','.','.','.','.','.','.','.',' ',' ','-','-','q','u','i','t','-','o','n','-','i','n','t','r','\n',
 ' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','E','x','i','t',' ','l','e','s','s',' ','i','n',' ','r','e','s','p','o','n','s','e',' ','t','o',' ','c','t','r','l','-','C','.','\n',
 ' ',' ','-','L',' ',' ','.','.','.','.','.','.','.','.',' ',' ','-','-','n','o','-','l','e','s','s','o','p','e','n','\n',
 ' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','I','g','n','o','r','e',' ','t','h','e',' ','L','E','S','S','O','P','E','N',' ','e','n','v','i','r','o','n','m','e','n','t',' ','v','a','r','i','a','b','l','e','.','\n',
@@ -206,12 +206,22 @@ constant char helpdata[] = {
 ' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','D','o','n','\'','t',' ','d','i','s','p','l','a','y',' ','t','i','l','d','e','s',' ','a','f','t','e','r',' ','e','n','d',' ','o','f',' ','f','i','l','e','.','\n',
 ' ',' ','-','#',' ','[','_','\b','N',']',' ',' ','.','.','.','.',' ',' ','-','-','s','h','i','f','t','=','[','_','\b','N',']','\n',
 ' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','H','o','r','i','z','o','n','t','a','l',' ','s','c','r','o','l','l',' ','a','m','o','u','n','t',' ','(','0',' ','=',' ','o','n','e',' ','h','a','l','f',' ','s','c','r','e','e','n',' ','w','i','d','t','h',')','\n',
-' ',' ',' ',' ',' ',' ','.','.','.','.','.','.','.','.',' ',' ','-','-','n','o','-','k','e','y','p','a','d','\n',
-' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','D','o','n','\'','t',' ','s','e','n','d',' ','t','e','r','m','c','a','p',' ','k','e','y','p','a','d',' ','i','n','i','t','/','d','e','i','n','i','t',' ','s','t','r','i','n','g','s','.','\n',
-' ',' ',' ',' ',' ',' ','.','.','.','.','.','.','.','.',' ',' ','-','-','f','o','l','l','o','w','-','n','a','m','e','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','-','-','f','o','l','l','o','w','-','n','a','m','e','\n',
 ' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','T','h','e',' ','F',' ','c','o','m','m','a','n','d',' ','c','h','a','n','g','e','s',' ','f','i','l','e','s',' ','i','f',' ','t','h','e',' ','i','n','p','u','t',' ','f','i','l','e',' ','i','s',' ','r','e','n','a','m','e','d','.','\n',
-' ',' ',' ',' ',' ',' ','.','.','.','.','.','.','.','.',' ',' ','-','-','u','s','e','-','b','a','c','k','s','l','a','s','h','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','-','-','m','o','u','s','e','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','E','n','a','b','l','e',' ','m','o','u','s','e',' ','i','n','p','u','t','.','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','-','-','n','o','-','k','e','y','p','a','d','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','D','o','n','\'','t',' ','s','e','n','d',' ','t','e','r','m','c','a','p',' ','k','e','y','p','a','d',' ','i','n','i','t','/','d','e','i','n','i','t',' ','s','t','r','i','n','g','s','.','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','-','-','n','o','-','h','i','s','t','d','u','p','s','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','R','e','m','o','v','e',' ','d','u','p','l','i','c','a','t','e','s',' ','f','r','o','m',' ','c','o','m','m','a','n','d',' ','h','i','s','t','o','r','y','.','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','-','-','r','s','c','r','o','l','l','=','C','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','S','e','t',' ','t','h','e',' ','c','h','a','r','a','c','t','e','r',' ','u','s','e','d',' ','t','o',' ','m','a','r','k',' ','t','r','u','n','c','a','t','e','d',' ','l','i','n','e','s','.','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','-','-','s','a','v','e','-','m','a','r','k','s','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','R','e','t','a','i','n',' ','m','a','r','k','s',' ','a','c','r','o','s','s',' ','i','n','v','o','c','a','t','i','o','n','s',' ','o','f',' ','l','e','s','s','.','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','-','-','u','s','e','-','b','a','c','k','s','l','a','s','h','\n',
 ' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','S','u','b','s','e','q','u','e','n','t',' ','o','p','t','i','o','n','s',' ','u','s','e',' ','b','a','c','k','s','l','a','s','h',' ','a','s',' ','e','s','c','a','p','e',' ','c','h','a','r','.','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','-','-','w','h','e','e','l','-','l','i','n','e','s','=','N','\n',
+' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ','E','a','c','h',' ','c','l','i','c','k',' ','o','f',' ','t','h','e',' ','m','o','u','s','e',' ','w','h','e','e','l',' ','m','o','v','e','s',' ','N',' ','l','i','n','e','s','.','\n',
 '\n',
 '\n',
 ' ','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','-','\n',
diff --git a/ifile.c b/ifile.c
index 613312b1c2a0..ceb59b773781 100644
--- a/ifile.c
+++ b/ifile.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -121,6 +121,12 @@ new_ifile(filename, prev)
 	p->h_hold = 0;
 	p->h_filestate = NULL;
 	link_ifile(p, prev);
+	/*
+	 * {{ It's dodgy to call mark.c functions from here;
+	 *    there is potentially dangerous recursion.
+	 *    Probably need to revisit this design. }}
+	 */
+	mark_check_ifile(ext_ifile(p));
 	return (p);
 }
 
@@ -198,7 +204,7 @@ getoff_ifile(ifile)
  * Return the number of ifiles.
  */
 	public int
-nifile()
+nifile(VOID_PARAM)
 {
 	return (ifiles);
 }
@@ -211,11 +217,26 @@ find_ifile(filename)
 	char *filename;
 {
 	struct ifile *p;
+	char *rfilename = lrealpath(filename);
 
 	for (p = anchor.h_next;  p != &anchor;  p = p->h_next)
-		if (strcmp(filename, p->h_filename) == 0)
-			return (p);
-	return (NULL);
+	{
+		if (strcmp(filename, p->h_filename) == 0 ||
+		    strcmp(rfilename, p->h_filename) == 0)
+		{
+			/*
+			 * If given name is shorter than the name we were
+			 * previously using for this file, adopt shorter name.
+			 */
+			if (strlen(filename) < strlen(p->h_filename))
+				strcpy(p->h_filename, filename);
+			break;
+		}
+	}
+	free(rfilename);
+	if (p == &anchor)
+		p = NULL;
+	return (p);
 }
 
 /*
@@ -365,7 +386,7 @@ get_altfilename(ifile)
 
 #if 0
 	public void
-if_dump()
+if_dump(VOID_PARAM)
 {
 	struct ifile *p;
 
diff --git a/input.c b/input.c
index 27be124c7417..8d0ebb151b7b 100644
--- a/input.c
+++ b/input.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
diff --git a/jump.c b/jump.c
index 2c7d28bd72c2..0e1d35d0e04f 100644
--- a/jump.c
+++ b/jump.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -26,7 +26,7 @@ extern int top_scroll;
  * Jump to the end of the file.
  */
 	public void
-jump_forw()
+jump_forw(VOID_PARAM)
 {
 	POSITION pos;
 	POSITION end_pos;
@@ -64,7 +64,7 @@ jump_forw()
  * Jump to the last buffered line in the file.
  */
 	public void
-jump_forw_buffered()
+jump_forw_buffered(VOID_PARAM)
 {
 	POSITION end;
 
@@ -115,7 +115,7 @@ jump_back(linenum)
  * Repaint the screen.
  */
 	public void
-repaint()
+repaint(VOID_PARAM)
 {
 	struct scrpos scrpos;
 	/*
diff --git a/less.h b/less.h
index 39ca65e2a4be..7ec58c3c1fdc 100644
--- a/less.h
+++ b/less.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -302,15 +302,6 @@ struct scrpos
 	int ln;
 };
 
-/*
- * A mark is an ifile (input file) plus a position within the file.
- */
-struct mark 
-{
-	IFILE m_ifile;
-	struct scrpos m_scrpos;
-};
-
 typedef union parg
 {
 	char *p_string;
@@ -471,6 +462,7 @@ struct wchar_range_table
 #endif /* IS_EBCDIC_HOST */
 
 #define	ESC		CONTROL('[')
+#define	ESCS		"\33"
 #define	CSI		((unsigned char)'\233')
 #define	CHAR_END_COMMAND 0x40000000
 
@@ -531,6 +523,15 @@ struct wchar_range_table
 #define	time_type	long
 #endif
 
+/* X11 mouse reporting definitions */
+#define X11MOUSE_BUTTON1    0 /* Left button press */
+#define X11MOUSE_BUTTON2    1 /* Middle button press */
+#define X11MOUSE_BUTTON3    2 /* Right button press */
+#define X11MOUSE_BUTTON_REL 3 /* Button release */
+#define X11MOUSE_WHEEL_UP   0x40 /* Wheel scroll up */
+#define X11MOUSE_WHEEL_DOWN 0x41 /* Wheel scroll down */
+#define X11MOUSE_OFFSET     0x20 /* Added to button & pos bytes to create a char */
+
 struct mlist;
 struct loption;
 struct hilite_tree;
@@ -541,3 +542,8 @@ struct hilite_tree;
 void postoa LESSPARAMS ((POSITION, char*));
 void linenumtoa LESSPARAMS ((LINENUM, char*));
 void inttoa LESSPARAMS ((int, char*));
+int lstrtoi LESSPARAMS ((char*, char**));
+POSITION lstrtopos LESSPARAMS ((char*, char**));
+#if MSDOS_COMPILER==WIN32C
+int pclose LESSPARAMS ((FILE*));
+#endif
diff --git a/less.hlp b/less.hlp
index 0bbada91bb94..a8f78adcdd7f 100644
--- a/less.hlp
+++ b/less.hlp
@@ -44,7 +44,7 @@
   ESC-u                Undo (toggle) search highlighting.
   &_p_a_t_t_e_r_n          *  Display only matching lines
         ---------------------------------------------------
-        A search pattern may be preceded by one or more of:
+        A search pattern may begin with one or more of:
         ^N or !  Search for NON-matching lines.
         ^E or *  Search multiple files (pass thru END OF FILE).
         ^F or @  Start search at FIRST file (for /) or last file (for ?).
@@ -153,7 +153,7 @@
                   Display a status column at left edge of screen.
   -k [_f_i_l_e]  .  --lesskey-file=[_f_i_l_e]
                   Use a lesskey file.
-  -K            --quit-on-intr
+  -K  ........  --quit-on-intr
                   Exit less in response to ctrl-C.
   -L  ........  --no-lessopen
                   Ignore the LESSOPEN environment variable.
@@ -203,12 +203,22 @@
                   Don't display tildes after end of file.
   -# [_N]  ....  --shift=[_N]
                   Horizontal scroll amount (0 = one half screen width)
-      ........  --no-keypad
-                  Don't send termcap keypad init/deinit strings.
-      ........  --follow-name
+                --follow-name
                   The F command changes files if the input file is renamed.
-      ........  --use-backslash
+                --mouse
+                  Enable mouse input.
+                --no-keypad
+                  Don't send termcap keypad init/deinit strings.
+                --no-histdups
+                  Remove duplicates from command history.
+                --rscroll=C
+                  Set the character used to mark truncated lines.
+                --save-marks
+                  Retain marks across invocations of less.
+                --use-backslash
                   Subsequent options use backslash as escape char.
+                --wheel-lines=N
+                  Each click of the mouse wheel moves N lines.
 
 
  ---------------------------------------------------------------------------
diff --git a/less.man b/less.man
index 84420a4e20b0..f0e178c7910e 100644
--- a/less.man
+++ b/less.man
@@ -718,96 +718,97 @@ LESS(1)                     General Commands Manual                    LESS(1)
 
        -Q or --QUIET or --SILENT
               Causes  totally  "quiet"  operation:  the terminal bell is never
-              rung.
+              rung.  If the terminal has a "visual bell", it is  used  in  all
+              cases where the terminal bell would have been rung.
 
        -r or --raw-control-chars
               Causes "raw" control characters to be displayed.  The default is
-              to  display  control  characters  using  the caret notation; for
+              to display control characters  using  the  caret  notation;  for
               example, a control-A (octal 001) is displayed as "^A".  Warning:
               when the -r option is used, less cannot keep track of the actual
-              appearance of the screen (since this depends on how  the  screen
+              appearance  of  the screen (since this depends on how the screen
               responds to each type of control character).  Thus, various dis-
-              play problems may result, such as long lines being split in  the
+              play  problems may result, such as long lines being split in the
               wrong place.
 
        -R or --RAW-CONTROL-CHARS
-              Like  -r,  but  only ANSI "color" escape sequences are output in
+              Like -r, but only ANSI "color" escape sequences  are  output  in
               "raw" form.  Unlike -r, the screen appearance is maintained cor-
               rectly  in  most  cases.   ANSI  "color"  escape  sequences  are
               sequences of the form:
 
                    ESC [ ... m
 
-              where the "..." is zero or more color  specification  characters
-              For  the  purpose  of  keeping  track of screen appearance, ANSI
-              color escape sequences are assumed to not move the cursor.   You
-              can  make less think that characters other than "m" can end ANSI
-              color escape  sequences  by  setting  the  environment  variable
+              where  the  "..." is zero or more color specification characters
+              For the purpose of keeping  track  of  screen  appearance,  ANSI
+              color  escape sequences are assumed to not move the cursor.  You
+              can make less think that characters other than "m" can end  ANSI
+              color  escape  sequences  by  setting  the  environment variable
               LESSANSIENDCHARS to the list of characters which can end a color
-              escape sequence.  And you can make less  think  that  characters
-              other  than the standard ones may appear between the ESC and the
-              m by setting the environment variable  LESSANSIMIDCHARS  to  the
+              escape  sequence.   And  you can make less think that characters
+              other than the standard ones may appear between the ESC and  the
+              m  by  setting  the environment variable LESSANSIMIDCHARS to the
               list of characters which can appear.
 
        -s or --squeeze-blank-lines
-              Causes  consecutive  blank  lines  to  be squeezed into a single
+              Causes consecutive blank lines to  be  squeezed  into  a  single
               blank line.  This is useful when viewing nroff output.
 
        -S or --chop-long-lines
-              Causes lines longer than the screen width to be  chopped  (trun-
+              Causes  lines  longer than the screen width to be chopped (trun-
               cated) rather than wrapped.  That is, the portion of a long line
               that does not fit in the screen width is not shown.  The default
-              is  to  wrap  long  lines; that is, display the remainder on the
+              is to wrap long lines; that is, display  the  remainder  on  the
               next line.
 
        -ttag or --tag=tag
               The -t option, followed immediately by a TAG, will edit the file
-              containing  that tag.  For this to work, tag information must be
-              available; for example, there may  be  a  file  in  the  current
+              containing that tag.  For this to work, tag information must  be
+              available;  for  example,  there  may  be  a file in the current
               directory called "tags", which was previously built by ctags (1)
               or an equivalent command.  If the environment variable LESSGLOB-
-              ALTAGS  is set, it is taken to be the name of a command compati-
-              ble with global (1), and that command is executed  to  find  the
+              ALTAGS is set, it is taken to be the name of a command  compati-
+              ble  with  global  (1), and that command is executed to find the
               tag.  (See http://www.gnu.org/software/global/global.html).  The
-              -t option may also be specified from within less  (using  the  -
-              command)  as a way of examining a new file.  The command ":t" is
+              -t  option  may  also be specified from within less (using the -
+              command) as a way of examining a new file.  The command ":t"  is
               equivalent to specifying -t from within less.
 
        -Ttagsfile or --tag-file=tagsfile
               Specifies a tags file to be used instead of "tags".
 
        -u or --underline-special
-              Causes backspaces and carriage returns to be treated  as  print-
-              able  characters;  that  is,  they are sent to the terminal when
+              Causes  backspaces  and carriage returns to be treated as print-
+              able characters; that is, they are sent  to  the  terminal  when
               they appear in the input.
 
        -U or --UNDERLINE-SPECIAL
-              Causes backspaces, tabs, carriage returns and "formatting  char-
+              Causes  backspaces, tabs, carriage returns and "formatting char-
               acters" (as defined by Unicode) to be treated as control charac-
               ters; that is, they are handled as specified by the -r option.
 
-              By default, if neither -u nor  -U  is  given,  backspaces  which
-              appear  adjacent  to  an  underscore  character are treated spe-
-              cially: the underlined text is displayed  using  the  terminal's
-              hardware  underlining capability.  Also, backspaces which appear
-              between two identical  characters  are  treated  specially:  the
-              overstruck  text  is printed using the terminal's hardware bold-
-              face capability.  Other backspaces are deleted, along  with  the
+              By  default,  if  neither  -u  nor -U is given, backspaces which
+              appear adjacent to an  underscore  character  are  treated  spe-
+              cially:  the  underlined  text is displayed using the terminal's
+              hardware underlining capability.  Also, backspaces which  appear
+              between  two  identical  characters  are  treated specially: the
+              overstruck text is printed using the terminal's  hardware  bold-
+              face  capability.   Other backspaces are deleted, along with the
               preceding character.  Carriage returns immediately followed by a
-              newline are deleted.  Other  carriage  returns  are  handled  as
-              specified  by the -r option.  Text which is overstruck or under-
+              newline  are  deleted.   Other  carriage  returns are handled as
+              specified by the -r option.  Text which is overstruck or  under-
               lined can be searched for if neither -u nor -U is in effect.
 
        -V or --version
               Displays the version number of less.
 
        -w or --hilite-unread
-              Temporarily highlights the first  "new"  line  after  a  forward
+              Temporarily  highlights  the  first  "new"  line after a forward
               movement of a full page.  The first "new" line is the line imme-
-              diately following the line  previously  at  the  bottom  of  the
+              diately  following  the  line  previously  at  the bottom of the
               screen.  Also highlights the target line after a g or p command.
-              The highlight is removed at the next command which causes  move-
-              ment.   The  entire line is highlighted, unless the -J option is
+              The  highlight is removed at the next command which causes move-
+              ment.  The entire line is highlighted, unless the -J  option  is
               in effect, in which case only the status column is highlighted.
 
        -W or --HILITE-UNREAD
@@ -815,48 +816,48 @@ LESS(1)                     General Commands Manual                    LESS(1)
               forward movement command larger than one line.
 
        -xn,... or --tabs=n,...
-              Sets  tab  stops.  If only one n is specified, tab stops are set
-              at multiples of n.  If multiple values separated by  commas  are
-              specified,  tab  stops are set at those positions, and then con-
-              tinue with the same spacing  as  the  last  two.   For  example,
-              -x9,17  will  set  tabs  at  positions  9, 17, 25, 33, etc.  The
+              Sets tab stops.  If only one n is specified, tab stops  are  set
+              at  multiples  of n.  If multiple values separated by commas are
+              specified, tab stops are set at those positions, and  then  con-
+              tinue  with  the  same  spacing  as  the last two.  For example,
+              -x9,17 will set tabs at positions  9,  17,  25,  33,  etc.   The
               default for n is 8.
 
        -X or --no-init
               Disables sending the termcap initialization and deinitialization
-              strings  to  the  terminal.   This is sometimes desirable if the
-              deinitialization string does something unnecessary, like  clear-
+              strings to the terminal.  This is  sometimes  desirable  if  the
+              deinitialization  string does something unnecessary, like clear-
               ing the screen.
 
        -yn or --max-forw-scroll=n
               Specifies a maximum number of lines to scroll forward.  If it is
-              necessary to scroll forward more than n  lines,  the  screen  is
-              repainted  instead.   The -c or -C option may be used to repaint
-              from the top of the screen if desired.  By default, any  forward
+              necessary  to  scroll  forward  more than n lines, the screen is
+              repainted instead.  The -c or -C option may be used  to  repaint
+              from  the top of the screen if desired.  By default, any forward
               movement causes scrolling.
 
        -zn or --window=n or -n
-              Changes  the  default  scrolling  window  size  to n lines.  The
+              Changes the default scrolling  window  size  to  n  lines.   The
               default is one screenful.  The z and w commands can also be used
-              to  change the window size.  The "z" may be omitted for compati-
+              to change the window size.  The "z" may be omitted for  compati-
               bility with some versions of more.  If the number n is negative,
-              it  indicates  n  lines  less than the current screen size.  For
+              it indicates n lines less than the  current  screen  size.   For
               example, if the screen is 24 lines, -z-4 sets the scrolling win-
-              dow  to  20  lines.   If  the screen is resized to 40 lines, the
+              dow to 20 lines.  If the screen is  resized  to  40  lines,  the
               scrolling window automatically changes to 36 lines.
 
        -"cc or --quotes=cc
-              Changes the filename quoting character.  This may  be  necessary
-              if  you are trying to name a file which contains both spaces and
-              quote characters.  Followed by a single character, this  changes
-              the  quote  character to that character.  Filenames containing a
+              Changes  the  filename quoting character.  This may be necessary
+              if you are trying to name a file which contains both spaces  and
+              quote  characters.  Followed by a single character, this changes
+              the quote character to that character.  Filenames  containing  a
               space should then be surrounded by that character rather than by
-              double  quotes.   Followed  by  two characters, changes the open
-              quote to the first character, and the close quote to the  second
+              double quotes.  Followed by two  characters,  changes  the  open
+              quote  to the first character, and the close quote to the second
               character.  Filenames containing a space should then be preceded
-              by the open quote character and  followed  by  the  close  quote
-              character.   Note  that  even  after  the  quote  characters are
-              changed, this option remains -" (a dash  followed  by  a  double
+              by  the  open  quote  character  and followed by the close quote
+              character.  Note  that  even  after  the  quote  characters  are
+              changed,  this  option  remains  -" (a dash followed by a double
               quote).
 
        -~ or --tilde
@@ -866,45 +867,75 @@ LESS(1)                     General Commands Manual                    LESS(1)
 
        -# or --shift
               Specifies the default number of positions to scroll horizontally
-              in the RIGHTARROW and LEFTARROW commands.  If the number  speci-
-              fied  is  zero,  it  sets the default number of positions to one
+              in  the RIGHTARROW and LEFTARROW commands.  If the number speci-
+              fied is zero, it sets the default number  of  positions  to  one
               half of the screen width.  Alternately, the number may be speci-
-              fied  as  a fraction of the width of the screen, starting with a
-              decimal point: .5 is half of  the  screen  width,  .3  is  three
-              tenths  of the screen width, and so on.  If the number is speci-
-              fied as a fraction, the actual number  of  scroll  positions  is
-              recalculated  if  the  terminal  window  is resized, so that the
-              actual scroll remains at the specified fraction  of  the  screen
+              fied as a fraction of the width of the screen, starting  with  a
+              decimal  point:  .5  is  half  of  the screen width, .3 is three
+              tenths of the screen width, and so on.  If the number is  speci-
+              fied  as  a  fraction,  the actual number of scroll positions is
+              recalculated if the terminal window  is  resized,  so  that  the
+              actual  scroll  remains  at the specified fraction of the screen
               width.
 
        --follow-name
-              Normally,  if  the  input  file is renamed while an F command is
-              executing, less will continue to display  the  contents  of  the
-              original  file  despite  its  name  change.  If --follow-name is
+              Normally, if the input file is renamed while  an  F  command  is
+              executing,  less  will  continue  to display the contents of the
+              original file despite its  name  change.   If  --follow-name  is
               specified, during an F command less will periodically attempt to
               reopen the file by name.  If the reopen succeeds and the file is
-              a different file from the original (which means that a new  file
-              has  been  created  with  the  same  name  as  the original (now
+              a  different file from the original (which means that a new file
+              has been created  with  the  same  name  as  the  original  (now
               renamed) file), less will display the contents of that new file.
 
+       --mouse
+              Enables  mouse  input: scrolling the mouse wheel down moves for-
+              ward in the file, scrolling the mouse wheel up  moves  backwards
+              in  the  file,  and  clicking the mouse sets the "#" mark to the
+              line where the mouse is clicked.  The number of lines to  scroll
+              when  the wheel is moved can be set by the --wheel-lines option.
+              Mouse input works only on  terminals  which  support  X11  mouse
+              reporting, and on the Windows version of less.
+
+       --MOUSE
+              Like --mouse, except the direction scrolled on mouse wheel move-
+              ment is reversed.
+
        --no-keypad
               Disables sending the keypad initialization and  deinitialization
               strings to the terminal.  This is sometimes useful if the keypad
               strings make the numeric keypad behave in an undesirable manner.
 
-       --use-backslash
-              This option changes the interpretations of options which  follow
-              this one.  After the --use-backslash option, any backslash in an
-              option string is removed and the following  character  is  taken
-              literally.   This  allows a dollar sign to be included in option
-              strings.
+       --no-histdups
+              This option changes the behavior so that if a search  string  or
+              file  name  is  typed  in, and the same string is already in the
+              history list, the existing copy is removed from the history list
+              before  the  new one is added.  Thus, a given string will appear
+              only once in the history list.  Normally, a  string  may  appear
+              multiple times.
 
        --rscroll
-              This option changes the character used to mark truncated  lines.
+              This  option changes the character used to mark truncated lines.
               It may begin with a two-character attribute indicator like LESS-
-              BINFMT does.  If there is no attribute  indicator,  standout  is
+              BINFMT  does.   If  there is no attribute indicator, standout is
               used.  If set to "-", truncated lines are not marked.
 
+       --save-marks
+              Save marks in the history file, so  marks  are  retained  across
+              different invocations of less.
+
+       --use-backslash
+              This  option changes the interpretations of options which follow
+              this one.  After the --use-backslash option, any backslash in an
+              option  string  is  removed and the following character is taken
+              literally.  This allows a dollar sign to be included  in  option
+              strings.
+
+       --wheel-lines=n
+              Set  the  number  of  lines  to  scroll  when the mouse wheel is
+              scrolled and the --mouse or --MOUSE option is  in  effect.   The
+              default is 1 line.
+
        --     A  command  line  argument of "--" marks the end of option argu-
               ments.  Any arguments following this are  interpreted  as  file-
               names.  This can be useful when viewing a file whose name begins
@@ -1077,11 +1108,12 @@ LESS(1)                     General Commands Manual                    LESS(1)
        lessopen.sh:
             #! /bin/sh
             case "$1" in
-            *.Z) uncompress -c $1  >/tmp/less.$$  2>/dev/null
-                 if [ -s /tmp/less.$$ ]; then
-                      echo /tmp/less.$$
+            *.Z) TEMPFILE=$(mktemp)
+                 uncompress -c $1  >$TEMPFILE  2>/dev/null
+                 if [ -s $TEMPFILE ]; then
+                      echo $TEMPFILE
                  else
-                      rm -f /tmp/less.$$
+                      rm -f $TEMPFILE
                  fi
                  ;;
             esac
@@ -1117,6 +1149,7 @@ LESS(1)                     General Commands Manual                    LESS(1)
             #! /bin/sh
             case "$1" in
             *.Z) uncompress -c $1  2>/dev/null
+                 ;;
             *)   exit 1
                  ;;
             esac
@@ -1317,6 +1350,10 @@ LESS(1)                     General Commands Manual                    LESS(1)
        %F     Replaced by the last component of the name of the current  input
               file.
 
+       %g     Replaced  by  the  shell-escaped name of the current input file.
+              This is useful when the expanded string will be used in a  shell
+              command, such as in LESSEDIT.
+
        %i     Replaced  by  the index of the current file in the list of input
               files.
 
@@ -1442,16 +1479,17 @@ LESS(1)                     General Commands Manual                    LESS(1)
        expanded in the same way as the prompt strings.  The default value  for
        LESSEDIT is:
 
-            %E ?lm+%lm. %f
+            %E ?lm+%lm. %g
 
        Note that this expands to the editor name, followed by a + and the line
-       number, followed by the file name.  If your editor does not accept  the
-       "+linenumber"  syntax,  or  has other differences in invocation syntax,
-       the LESSEDIT variable can be changed to modify this default.
+       number, followed by the shell-escaped file name.  If your  editor  does
+       not  accept the "+linenumber" syntax, or has other differences in invo-
+       cation syntax, the LESSEDIT variable can  be  changed  to  modify  this
+       default.
 
 
 SECURITY
-       When the environment variable LESSSECURE is set to 1, less  runs  in  a
+       When  the  environment  variable LESSSECURE is set to 1, less runs in a
        "secure" mode.  This means these features are disabled:
 
               !      the shell command
@@ -1477,54 +1515,54 @@ LESS(1)                     General Commands Manual                    LESS(1)
 
 COMPATIBILITY WITH MORE
        If the environment variable LESS_IS_MORE is set to 1, or if the program
-       is invoked via a file link named "more", less behaves (mostly) in  con-
-       formance  with  the  POSIX "more" command specification.  In this mode,
+       is  invoked via a file link named "more", less behaves (mostly) in con-
+       formance with the POSIX "more" command specification.   In  this  mode,
        less behaves differently in these ways:
 
-       The -e option works differently.  If the -e option  is  not  set,  less
-       behaves  as  if  the -e option were set.  If the -e option is set, less
+       The  -e  option  works  differently.  If the -e option is not set, less
+       behaves as if the -e option were set.  If the -e option  is  set,  less
        behaves as if the -E option were set.
 
-       The -m option works differently.  If the -m  option  is  not  set,  the
-       medium  prompt  is used, and it is prefixed with the string "--More--".
+       The  -m  option  works  differently.   If the -m option is not set, the
+       medium prompt is used, and it is prefixed with the  string  "--More--".
        If the -m option is set, the short prompt is used.
 
-       The -n option acts like the -z option.  The normal behavior of  the  -n
+       The  -n  option acts like the -z option.  The normal behavior of the -n
        option is unavailable in this mode.
 
-       The  parameter  to  the  -p option is taken to be a less command rather
+       The parameter to the -p option is taken to be  a  less  command  rather
        than a search pattern.
 
-       The LESS environment variable is  ignored,  and  the  MORE  environment
+       The  LESS  environment  variable  is  ignored, and the MORE environment
        variable is used in its place.
 
 
 ENVIRONMENT VARIABLES
        Environment variables may be specified either in the system environment
-       as usual, or in a lesskey  (1)  file.   If  environment  variables  are
-       defined  in  more  than one place, variables defined in a local lesskey
-       file take precedence over variables defined in the system  environment,
+       as  usual,  or  in  a  lesskey  (1) file.  If environment variables are
+       defined in more than one place, variables defined in  a  local  lesskey
+       file  take precedence over variables defined in the system environment,
        which take precedence over variables defined in the system-wide lesskey
        file.
 
        COLUMNS
               Sets the number of columns on the screen.  Takes precedence over
-              the  number  of columns specified by the TERM variable.  (But if
+              the number of columns specified by the TERM variable.   (But  if
               you  have  a  windowing  system  which  supports  TIOCGWINSZ  or
-              WIOCGETD,  the  window  system's  idea  of the screen size takes
+              WIOCGETD, the window system's idea  of  the  screen  size  takes
               precedence over the LINES and COLUMNS environment variables.)
 
        EDITOR The name of the editor (used for the v command).
 
-       HOME   Name of the user's home directory (used to find a  lesskey  file
+       HOME   Name  of  the user's home directory (used to find a lesskey file
               on Unix and OS/2 systems).
 
        HOMEDRIVE, HOMEPATH
-              Concatenation  of  the  HOMEDRIVE and HOMEPATH environment vari-
+              Concatenation of the HOMEDRIVE and  HOMEPATH  environment  vari-
               ables is the name of the user's home directory if the HOME vari-
               able is not set (only in the Windows version).
 
-       INIT   Name  of  the user's init directory (used to find a lesskey file
+       INIT   Name of the user's init directory (used to find a  lesskey  file
               on OS/2 systems).
 
        LANG   Language for determining the character set.
@@ -1535,12 +1573,12 @@ LESS(1)                     General Commands Manual                    LESS(1)
        LESS   Options which are passed to less automatically.
 
        LESSANSIENDCHARS
-              Characters which may end an ANSI color escape sequence  (default
+              Characters  which may end an ANSI color escape sequence (default
               "m").
 
        LESSANSIMIDCHARS
-              Characters  which  may  appear between the ESC character and the
-              end  character  in  an  ANSI  color  escape  sequence   (default
+              Characters which may appear between the ESC  character  and  the
+              end   character  in  an  ANSI  color  escape  sequence  (default
               "0123456789:;[?!"'#%()*+ ".
 
        LESSBINFMT
@@ -1557,24 +1595,24 @@ LESS(1)                     General Commands Manual                    LESS(1)
 
        LESSECHO
               Name of the lessecho program (default "lessecho").  The lessecho
-              program is needed to expand metacharacters, such as * and ?,  in
+              program  is needed to expand metacharacters, such as * and ?, in
               filenames on Unix systems.
 
        LESSEDIT
-              Editor  prototype  string (used for the v command).  See discus-
+              Editor prototype string (used for the v command).   See  discus-
               sion under PROMPTS.
 
        LESSGLOBALTAGS
-              Name of the command used by the -t option to find  global  tags.
+              Name  of  the command used by the -t option to find global tags.
               Normally should be set to "global" if your system has the global
               (1) command.  If not set, global tags are not used.
 
        LESSHISTFILE
-              Name of the history file used to remember  search  commands  and
-              shell  commands  between  invocations of less.  If set to "-" or
-              "/dev/null", a  history  file  is  not  used.   The  default  is
-              "$HOME/.lesshst"  on  Unix  systems, "$HOME/_lesshst" on DOS and
-              Windows systems, or "$HOME/lesshst.ini"  or  "$INIT/lesshst.ini"
+              Name  of  the  history file used to remember search commands and
+              shell commands between invocations of less.  If set  to  "-"  or
+              "/dev/null",  a  history  file  is  not  used.   The  default is
+              "$HOME/.lesshst" on Unix systems, "$HOME/_lesshst"  on  DOS  and
+              Windows  systems,  or "$HOME/lesshst.ini" or "$INIT/lesshst.ini"
               on OS/2 systems.
 
        LESSHISTSIZE
@@ -1588,13 +1626,13 @@ LESS(1)                     General Commands Manual                    LESS(1)
               Name of the default system-wide lesskey(1) file.
 
        LESSMETACHARS
-              List of characters which are considered "metacharacters" by  the
+              List  of characters which are considered "metacharacters" by the
               shell.
 
        LESSMETAESCAPE
-              Prefix  which  less will add before each metacharacter in a com-
-              mand sent to the shell.  If LESSMETAESCAPE is an  empty  string,
-              commands  containing  metacharacters  will  not be passed to the
+              Prefix which less will add before each metacharacter in  a  com-
+              mand  sent  to the shell.  If LESSMETAESCAPE is an empty string,
+              commands containing metacharacters will not  be  passed  to  the
               shell.
 
        LESSOPEN
@@ -1604,7 +1642,7 @@ LESS(1)                     General Commands Manual                    LESS(1)
               Runs less in "secure" mode.  See discussion under SECURITY.
 
        LESSSEPARATOR
-              String to be appended to a directory name  in  filename  comple-
+              String  to  be  appended to a directory name in filename comple-
               tion.
 
        LESSUTFBINFMT
@@ -1613,19 +1651,19 @@ LESS(1)                     General Commands Manual                    LESS(1)
        LESS_IS_MORE
               Emulate the more (1) command.
 
-       LINES  Sets  the  number of lines on the screen.  Takes precedence over
+       LINES  Sets the number of lines on the screen.  Takes  precedence  over
               the number of lines specified by the TERM variable.  (But if you
-              have  a  windowing system which supports TIOCGWINSZ or WIOCGETD,
-              the window system's idea of the  screen  size  takes  precedence
+              have a windowing system which supports TIOCGWINSZ  or  WIOCGETD,
+              the  window  system's  idea  of the screen size takes precedence
               over the LINES and COLUMNS environment variables.)
 
-       MORE   Options  which  are passed to less automatically when running in
+       MORE   Options which are passed to less automatically when  running  in
               more compatible mode.
 
-       PATH   User's search path (used to find a lesskey file  on  MS-DOS  and
+       PATH   User's  search  path  (used to find a lesskey file on MS-DOS and
               OS/2 systems).
 
-       SHELL  The  shell  used  to execute the ! command, as well as to expand
+       SHELL  The shell used to execute the ! command, as well  as  to  expand
               filenames.
 
        TERM   The type of terminal on which less is being run.
@@ -1638,32 +1676,30 @@ LESS(1)                     General Commands Manual                    LESS(1)
 
 
 COPYRIGHT
-       Copyright (C) 1984-2017  Mark Nudelman
+       Copyright (C) 1984-2019  Mark Nudelman
 
-       less is part of the GNU project and is free software.  You  can  redis-
-       tribute  it and/or modify it under the terms of either (1) the GNU Gen-
-       eral Public License as published by the Free  Software  Foundation;  or
+       less  is  part of the GNU project and is free software.  You can redis-
+       tribute it and/or modify it under the terms of either (1) the GNU  Gen-
+       eral  Public  License  as published by the Free Software Foundation; or
        (2) the Less License.  See the file README in the less distribution for
        more details regarding redistribution.  You should have received a copy
-       of  the  GNU General Public License along with the source for less; see
-       the file COPYING.  If not, write to the Free  Software  Foundation,  59
-       Temple  Place, Suite 330, Boston, MA  02111-1307, USA.  You should also
+       of the GNU General Public License along with the source for  less;  see
+       the  file  COPYING.   If not, write to the Free Software Foundation, 59
+       Temple Place, Suite 330, Boston, MA  02111-1307, USA.  You should  also
        have received a copy of the Less License; see the file LICENSE.
 
        less is distributed in the hope that it will be useful, but WITHOUT ANY
-       WARRANTY;  without even the implied warranty of MERCHANTABILITY or FIT-
-       NESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License  for
+       WARRANTY; without even the implied warranty of MERCHANTABILITY or  FIT-
+       NESS  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
        more details.
 
 
 AUTHOR
        Mark Nudelman
-       Send bug reports or comments to <bug-less@gnu.org>
-       See http://www.greenwoodsoftware.com/less/bugs.html for the latest list
-       of known bugs in less.
+       Report bugs at https://github.com/gwsw/less/issues.
        For more information, see the less homepage at
        http://www.greenwoodsoftware.com/less.
 
 
 
-                           Version 530: 05 Dec 2017                    LESS(1)
+                           Version 551: 11 Jun 2019                    LESS(1)
diff --git a/less.nro b/less.nro
index fa0b4ffff91b..0aa8b7863330 100644
--- a/less.nro
+++ b/less.nro
@@ -1,4 +1,4 @@
-.TH LESS 1 "Version 530: 05 Dec 2017"
+.TH LESS 1 "Version 551: 11 Jun 2019"
 .SH NAME
 less \- opposite of more
 .SH SYNOPSIS
@@ -762,6 +762,8 @@ The default is to ring the terminal bell in all such cases.
 .IP "\-Q or \-\-QUIET or \-\-SILENT"
 Causes totally "quiet" operation:
 the terminal bell is never rung.
+If the terminal has a "visual bell", it is used in all cases 
+where the terminal bell would have been rung.
 .IP "\-r or \-\-raw-control-chars"
 Causes "raw" control characters to be displayed.
 The default is to display control characters using the caret notation;
@@ -938,21 +940,48 @@ If the reopen succeeds and the file is a different file from the original
 with the same name as the original (now renamed) file),
 .I less
 will display the contents of that new file.
+.IP "\-\-mouse"
+Enables mouse input:
+scrolling the mouse wheel down moves forward in the file,
+scrolling the mouse wheel up moves backwards in the file,
+and clicking the mouse sets the "#" mark to the line 
+where the mouse is clicked.
+The number of lines to scroll when the wheel is moved 
+can be set by the \-\-wheel-lines option.
+Mouse input works only on terminals which support X11 mouse reporting,
+and on the Windows version of 
+.IR less .
+.IP "\-\-MOUSE"
+Like \-\-mouse, except the direction scrolled 
+on mouse wheel movement is reversed.
 .IP "\-\-no-keypad"
 Disables sending the keypad initialization and deinitialization strings
 to the terminal.
 This is sometimes useful if the keypad strings make the numeric
 keypad behave in an undesirable manner.
-.IP "\-\-use-backslash"
-This option changes the interpretations of options which follow this one.
-After the \-\-use-backslash option, any backslash in an option string is
-removed and the following character is taken literally.
-This allows a dollar sign to be included in option strings.
+.IP "\-\-no-histdups"
+This option changes the behavior so that if a search string or
+file name is typed in, and the same string is already in the history list, 
+the existing copy is removed from the history list before the new one is added.
+Thus, a given string will appear only once in the history list.
+Normally, a string may appear multiple times.
 .IP "\-\-rscroll"
 This option changes the character used to mark truncated lines.
 It may begin with a two-character attribute indicator like LESSBINFMT does.
 If there is no attribute indicator, standout is used.
 If set to "-", truncated lines are not marked.
+.IP "\-\-save-marks"
+Save marks in the history file, so marks are retained
+across different invocations of \fIless\fP.
+.IP "\-\-use-backslash"
+This option changes the interpretations of options which follow this one.
+After the \-\-use-backslash option, any backslash in an option string is
+removed and the following character is taken literally.
+This allows a dollar sign to be included in option strings.
+.IP "\-\-wheel-lines=\fIn\fP"
+Set the number of lines to scroll when the mouse wheel is scrolled
+and the \-\-mouse or \-\-MOUSE option is in effect.
+The default is 1 line.
 .IP \-\-
 A command line argument of "\-\-" marks the end of option arguments.
 Any arguments following this are interpreted as filenames.
@@ -1154,15 +1183,17 @@ lessopen.sh:
 .br
 	case "$1" in
 .br
-	*.Z)	uncompress \-c $1  >/tmp/less.$$  2>/dev/null
+	*.Z)	TEMPFILE=$(mktemp)
+.br
+		uncompress \-c $1  >$TEMPFILE  2>/dev/null
 .br
-		if [ \-s /tmp/less.$$ ]; then
+		if [ \-s $TEMPFILE ]; then
 .br
-			echo /tmp/less.$$
+			echo $TEMPFILE
 .br
 		else
 .br
-			rm \-f /tmp/less.$$
+			rm \-f $TEMPFILE
 .br
 		fi
 .br
@@ -1213,6 +1244,8 @@ lesspipe.sh:
 .br
 	*.Z)	uncompress \-c $1  2>/dev/null
 .br
+		;;
+.br
 	*)	exit 1
 .br
 		;;
@@ -1440,6 +1473,10 @@ See the discussion of the LESSEDIT feature below.
 Replaced by the name of the current input file.
 .IP "%F"
 Replaced by the last component of the name of the current input file.
+.IP "%g"
+Replaced by the shell-escaped name of the current input file.
+This is useful when the expanded string will be used in a shell command,
+such as in LESSEDIT.
 .IP "%i"
 Replaced by the index of the current file in the list of
 input files.
@@ -1575,11 +1612,11 @@ The LESSEDIT string is expanded in the same way as the prompt strings.
 The default value for LESSEDIT is:
 .nf
 .sp
-	%E\ ?lm+%lm.\ %f
+	%E\ ?lm+%lm.\ %g
 .sp
 .fi
 Note that this expands to the editor name, followed by a + and the
-line number, followed by the file name.
+line number, followed by the shell-escaped file name.
 If your editor does not accept the "+linenumber" syntax, or has other
 differences in invocation syntax, the LESSEDIT variable can be
 changed to modify this default.
@@ -1766,7 +1803,7 @@ The name of the editor (used for the v command).
 lesskey(1)
 
 .SH COPYRIGHT
-Copyright (C) 1984-2017  Mark Nudelman
+Copyright (C) 1984-2019  Mark Nudelman
 .PP
 less is part of the GNU project and is free software.
 You can redistribute it and/or modify it
@@ -1791,9 +1828,7 @@ See the GNU General Public License for more details.
 .PP
 Mark Nudelman
 .br
-Send bug reports or comments to <bug-less@gnu.org>
-.br
-See http://www.greenwoodsoftware.com/less/bugs.html for the latest list of known bugs in less.
+Report bugs at https://github.com/gwsw/less/issues.
 .br
 For more information, see the less homepage at
 .br
diff --git a/lessecho.c b/lessecho.c
index 4ed4830e1641..2f4a10eed109 100644
--- a/lessecho.c
+++ b/lessecho.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -38,14 +38,14 @@ static char metachars[64] = "";
 static int num_metachars = 0;
 
 	static void
-pr_usage()
+pr_usage(VOID_PARAM)
 {
 	fprintf(stderr,
 		"usage: lessecho [-ox] [-cx] [-pn] [-dn] [-mx] [-nn] [-ex] [-fn] [-a] file ...\n");
 }
 
 	static void
-pr_version()
+pr_version(VOID_PARAM)
 {
 	char *p;
 	char buf[10];
diff --git a/lessecho.man b/lessecho.man
index de4200ce4dad..6a26991031f3 100644
--- a/lessecho.man
+++ b/lessecho.man
@@ -51,4 +51,4 @@ LESSECHO(1)                 General Commands Manual                LESSECHO(1)
 
 
 
-                           Version 530: 05 Dec 2017                LESSECHO(1)
+                           Version 551: 11 Jun 2019                LESSECHO(1)
diff --git a/lessecho.nro b/lessecho.nro
index 49a97fff163b..4fe997e8b1cd 100644
--- a/lessecho.nro
+++ b/lessecho.nro
@@ -1,4 +1,4 @@
-.TH LESSECHO 1 "Version 530: 05 Dec 2017"
+.TH LESSECHO 1 "Version 551: 11 Jun 2019"
 .SH NAME
 lessecho \- expand metacharacters
 .SH SYNOPSIS
diff --git a/lesskey.c b/lesskey.c
index fa1ab6d3a452..96a446228dee 100644
--- a/lesskey.c
+++ b/lesskey.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -220,7 +220,7 @@ int errors;
 extern char version[];
 
 	void
-usage()
+usage(VOID_PARAM)
 {
 	fprintf(stderr, "usage: lesskey [-o output] [input]\n");
 	exit(1);
@@ -343,7 +343,7 @@ parse_args(argc, argv)
  * Initialize data structures.
  */
 	void
-init_tables()
+init_tables(VOID_PARAM)
 {
 	cmdtable.names = cmdnames;
 	cmdtable.pbuffer = cmdtable.buffer;
diff --git a/lesskey.h b/lesskey.h
index 92d4d93af179..299bf4526110 100644
--- a/lesskey.h
+++ b/lesskey.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
diff --git a/lesskey.man b/lesskey.man
index 99e5f16dc3ff..68af6c42298d 100644
--- a/lesskey.man
+++ b/lesskey.man
@@ -337,7 +337,7 @@ LESSKEY(1)                  General Commands Manual                 LESSKEY(1)
 
 
 COPYRIGHT
-       Copyright (C) 1984-2017  Mark Nudelman
+       Copyright (C) 1984-2019  Mark Nudelman
 
        less  is  part of the GNU project and is free software.  You can redis-
        tribute it and/or modify it under the terms of either (1) the GNU  Gen-
@@ -361,4 +361,4 @@ LESSKEY(1)                  General Commands Manual                 LESSKEY(1)
 
 
 
-                           Version 530: 05 Dec 2017                 LESSKEY(1)
+                           Version 551: 11 Jun 2019                 LESSKEY(1)
diff --git a/lesskey.nro b/lesskey.nro
index ffe520be37a6..48aec7f6982a 100644
--- a/lesskey.nro
+++ b/lesskey.nro
@@ -1,4 +1,4 @@
-.TH LESSKEY 1 "Version 530: 05 Dec 2017"
+.TH LESSKEY 1 "Version 551: 11 Jun 2019"
 .SH NAME
 lesskey \- specify key bindings for less
 .SH SYNOPSIS
@@ -363,7 +363,7 @@ which start with a NUL character (0).
 This NUL character should be represented as \e340 in a lesskey file.
 
 .SH COPYRIGHT
-Copyright (C) 1984-2017  Mark Nudelman
+Copyright (C) 1984-2019  Mark Nudelman
 .PP
 less is part of the GNU project and is free software.
 You can redistribute it and/or modify it
diff --git a/lglob.h b/lglob.h
index 0d9fb5b989bc..ed44fcc7b9f2 100644
--- a/lglob.h
+++ b/lglob.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -56,7 +56,7 @@
 					char ext[_MAX_EXT];	\
 					int handle;
 #else
-#if MSDOS_COMPILER==WIN32C && defined(_MSC_VER)
+#if MSDOS_COMPILER==WIN32C && (defined(_MSC_VER) || defined(MINGW))
 
 #define	GLOB_FIRST_NAME(filename,fndp,h) h = _findfirst(filename, fndp)
 #define	GLOB_FIRST_FAILED(handle)	((handle) == -1)
diff --git a/line.c b/line.c
index dd890f3db3ff..02a2d8679e29 100644
--- a/line.c
+++ b/line.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -67,7 +67,7 @@ extern int sc_width, sc_height;
 extern int utf_mode;
 extern POSITION start_attnpos;
 extern POSITION end_attnpos;
-extern LWCHAR rscroll_char;
+extern char rscroll_char;
 extern int rscroll_attr;
 
 static char mbc_buf[MAX_UTF_CHAR_LEN];
@@ -79,14 +79,14 @@ static POSITION mbc_pos;
  * Initialize from environment variables.
  */
 	public void
-init_line()
+init_line(VOID_PARAM)
 {
 	end_ansi_chars = lgetenv("LESSANSIENDCHARS");
-	if (end_ansi_chars == NULL || *end_ansi_chars == '\0')
+	if (isnullenv(end_ansi_chars))
 		end_ansi_chars = "m";
 
 	mid_ansi_chars = lgetenv("LESSANSIMIDCHARS");
-	if (mid_ansi_chars == NULL || *mid_ansi_chars == '\0')
+	if (isnullenv(mid_ansi_chars))
 		mid_ansi_chars = "0123456789:;[?!\"'#%()*+ ";
 
 	linebuf = (char *) ecalloc(LINEBUF_SIZE, sizeof(char));
@@ -98,7 +98,7 @@ init_line()
  * Expand the line buffer.
  */
 	static int
-expand_linebuf()
+expand_linebuf(VOID_PARAM)
 {
 	/* Double the size of the line buffer. */
 	int new_size = size_linebuf * 2;
@@ -119,15 +119,7 @@ expand_linebuf()
 			free(new_buf);
 		return 1;
 	}
-#if HAVE_REALLOC
-	/*
-	 * We realloc'd the buffers; they already have the old contents.
-	 */
-	#if 0
-	memset(new_buf + size_linebuf, 0, new_size - size_linebuf);
-	memset(new_attr + size_linebuf, 0, new_size - size_linebuf);
-	#endif
-#else
+#if !HAVE_REALLOC
 	/*
 	 * We just calloc'd the buffers; copy the old contents.
 	 */
@@ -156,7 +148,7 @@ is_ascii_char(ch)
  * Rewind the line buffer.
  */
 	public void
-prewind()
+prewind(VOID_PARAM)
 {
 	curr = 0;
 	column = 0;
@@ -179,7 +171,7 @@ prewind()
 	static void
 set_linebuf(n, ch, a)
 	int n;
-	LWCHAR ch;
+	char ch;
 	char a;
 {
 	linebuf[n] = ch;
@@ -191,7 +183,7 @@ set_linebuf(n, ch, a)
  */
 	static void
 add_linebuf(ch, a, w)
-	LWCHAR ch;
+	char ch;
 	char a;
 	int w;
 {
@@ -395,7 +387,7 @@ pshift(shift)
  *
  */
 	public void
-pshift_all()
+pshift_all(VOID_PARAM)
 {
 	pshift(column);
 }
@@ -519,7 +511,7 @@ pwidth(ch, a, prev_ch)
  * Return 1 if one is found.
  */
 	static int
-backc()
+backc(VOID_PARAM)
 {
 	LWCHAR prev_ch;
 	char *p = linebuf + curr;
@@ -547,7 +539,7 @@ backc()
  * Are we currently within a recognized ANSI escape sequence?
  */
 	static int
-in_ansi_esc_seq()
+in_ansi_esc_seq(VOID_PARAM)
 {
 	char *p;
 
@@ -1046,7 +1038,7 @@ do_append(ch, rep, pos)
  *
  */
 	public int
-pflushmbc()
+pflushmbc(VOID_PARAM)
 {
 	int r = 0;
 
@@ -1063,7 +1055,7 @@ pflushmbc()
  * Switch to normal attribute at end of line.
  */
 	static void
-add_attr_normal()
+add_attr_normal(VOID_PARAM)
 {
 	char *p = "\033[m";
 
@@ -1215,7 +1207,7 @@ gline(i, ap)
  * Indicate that there is no current line.
  */
 	public void
-null_line()
+null_line(VOID_PARAM)
 {
 	is_null_line = 1;
 	cshift = 0;
@@ -1349,7 +1341,7 @@ back_raw_line(curr_pos, linep, line_lenp)
  * Find the shift necessary to show the end of the longest displayed line.
  */
 	public int
-rrshift()
+rrshift(VOID_PARAM)
 {
 	POSITION pos;
 	int save_width;
diff --git a/linenum.c b/linenum.c
index 4e726377e38d..6a5560b627df 100644
--- a/linenum.c
+++ b/linenum.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -73,7 +73,7 @@ extern int screen_trashed;
  * Initialize the line number structures.
  */
 	public void
-clr_linenum()
+clr_linenum(VOID_PARAM)
 {
 	struct linenum_info *p;
 
@@ -209,7 +209,7 @@ add_lnum(linenum, pos)
  * line number, print a message to tell the user what we're doing.
  */
 	static void
-longloopmessage()
+longloopmessage(VOID_PARAM)
 {
 	ierror("Calculating line numbers", NULL_PARG);
 }
@@ -220,7 +220,7 @@ static time_type startime;
 #endif
 
 	static void
-longish()
+longish(VOID_PARAM)
 {
 #if HAVE_TIME
 	if (loopcount >= 0 && ++loopcount > 100)
@@ -246,7 +246,7 @@ longish()
  * a lengthy line number calculation.
  */
 	static void
-abort_long()
+abort_long(VOID_PARAM)
 {
 	if (linenums == OPT_ONPLUS)
 		/*
diff --git a/lsystem.c b/lsystem.c
index 10911ebe15d4..d4f1e7731379 100644
--- a/lsystem.c
+++ b/lsystem.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -19,6 +19,10 @@
 
 #if MSDOS_COMPILER
 #include <dos.h>
+#if MSDOS_COMPILER==WIN32C && defined(MINGW)
+#include <direct.h>
+#define setdisk(n) _chdrive((n)+1)
+#else
 #ifdef _MSC_VER
 #include <direct.h>
 #define setdisk(n) _chdrive((n)+1)
@@ -26,6 +30,7 @@
 #include <dir.h>
 #endif
 #endif
+#endif
 
 extern int screen_trashed;
 extern IFILE curr_ifile;
@@ -291,7 +296,6 @@ pipe_data(cmd, spos, epos)
 {
 	FILE *f;
 	int c;
-	extern FILE *popen();
 
 	/*
 	 * This is structured much like lsystem().
diff --git a/main.c b/main.c
index 179bd78c4331..c527e61936a1 100644
--- a/main.c
+++ b/main.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -14,6 +14,7 @@
 
 #include "less.h"
 #if MSDOS_COMPILER==WIN32C
+#define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 #endif
 
@@ -53,12 +54,13 @@ extern int	jump_sline;
 static char consoleTitle[256];
 #endif
 
-public int  line_count;
+public int	one_screen;
 extern int	less_is_more;
 extern int	missing_cap;
 extern int	know_dumb;
 extern int	pr_type;
 extern int	quit_if_one_screen;
+extern int	no_init;
 
 
 /*
@@ -82,7 +84,7 @@ main(argc, argv)
 
 	secure = 0;
 	s = lgetenv("LESSSECURE");
-	if (s != NULL && *s != '\0')
+	if (!isnullenv(s))
 		secure = 1;
 
 #ifdef WIN32
@@ -112,6 +114,7 @@ main(argc, argv)
 	 * Command line arguments override environment arguments.
 	 */
 	is_tty = isatty(1);
+	init_mark();
 	init_cmds();
 	get_term();
 	expand_cmd_tables();
@@ -125,11 +128,7 @@ main(argc, argv)
 	 * If the name of the executable program is "more",
 	 * act like LESS_IS_MORE is set.
 	 */
-	for (s = progname + strlen(progname);  s > progname;  s--)
-	{
-		if (s[-1] == PATHNAME_SEP[0])
-			break;
-	}
+	s = last_component(progname);
 	if (strcmp(s, "more") == 0)
 		less_is_more = 1;
 
@@ -165,12 +164,12 @@ main(argc, argv)
 	if (editor == NULL || *editor == '\0')
 	{
 		editor = lgetenv("EDITOR");
-		if (editor == NULL || *editor == '\0')
+		if (isnullenv(editor))
 			editor = EDIT_PGM;
 	}
 	editproto = lgetenv("LESSEDIT");
-	if (editproto == NULL || *editproto == '\0')
-		editproto = "%E ?lm+%lm. %f";
+	if (isnullenv(editproto))
+		editproto = "%E ?lm+%lm. %g";
 #endif
 
 	/*
@@ -220,11 +219,7 @@ main(argc, argv)
 		 * Just copy the input file(s) to output.
 		 */
 		SET_BINARY(1);
-		if (nifile() == 0)
-		{
-			if (edit_stdin() == 0)
-				cat_file();
-		} else if (edit_first() == 0)
+		if (edit_first() == 0)
 		{
 			do {
 				cat_file();
@@ -235,7 +230,6 @@ main(argc, argv)
 
 	if (missing_cap && !know_dumb)
 		error("WARNING: terminal is not fully functional", NULL_PARG);
-	init_mark();
 	open_getchr();
 	raw_mode(1);
 	init_signals(1);
@@ -270,22 +264,20 @@ main(argc, argv)
 		initial_scrpos.ln = jump_sline;
 	} else
 #endif
-	if (nifile() == 0)
-	{
-		if (edit_stdin())  /* Edit standard input */
-			quit(QUIT_ERROR);
-		if (quit_if_one_screen)
-			line_count = get_line_count();
-	} else 
 	{
-		if (edit_first())  /* Edit first valid file in cmd line */
+		if (edit_first())
 			quit(QUIT_ERROR);
+		/*
+		 * See if file fits on one screen to decide whether 
+		 * to send terminal init. But don't need this 
+		 * if -X (no_init) overrides this (see init()).
+		 */
 		if (quit_if_one_screen)
 		{
-			if (nifile() == 1)
-				line_count = get_line_count();
-			else /* If more than one file, -F can not be used */
+			if (nifile() > 1) /* If more than one file, -F cannot be used */
 				quit_if_one_screen = FALSE;
+			else if (!no_init)
+				one_screen = get_one_screen();
 		}
 	}
 
diff --git a/mark.c b/mark.c
index fbdac6e3f461..92cb8ceaabfe 100644
--- a/mark.c
+++ b/mark.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -14,30 +14,103 @@
 extern IFILE curr_ifile;
 extern int sc_height;
 extern int jump_sline;
+extern int perma_marks;
+
+/*
+ * A mark is an ifile (input file) plus a position within the file.
+ */
+struct mark 
+{
+	/*
+	 * Normally m_ifile != IFILE_NULL and m_filename == NULL.
+	 * For restored marks we set m_filename instead of m_ifile
+	 * because we don't want to create an ifile until the 
+	 * user explicitly requests the file (by name or mark).
+	 */
+	char m_letter;           /* Associated character */
+	IFILE m_ifile;           /* Input file being marked */
+	char *m_filename;        /* Name of the input file */
+	struct scrpos m_scrpos;  /* Position of the mark */
+};
 
 /*
  * The table of marks.
  * Each mark is identified by a lowercase or uppercase letter.
  * The final one is lmark, for the "last mark"; addressed by the apostrophe.
  */
-#define	NMARKS		((2*26)+1)	/* a-z, A-Z, lastmark */
+#define	NMARKS		((2*26)+2)	/* a-z, A-Z, mousemark, lastmark */
+#define	NUMARKS		((2*26)+1)	/* user marks (not lastmark) */
+#define	MOUSEMARK	(NMARKS-2)
 #define	LASTMARK	(NMARKS-1)
 static struct mark marks[NMARKS];
+public int marks_modified = 0;
+
+
+/*
+ * Initialize a mark struct.
+ */
+	static void
+cmark(m, ifile, pos, ln)
+	struct mark *m;
+	IFILE ifile;
+	POSITION pos;
+	int ln;
+{
+	m->m_ifile = ifile;
+	m->m_scrpos.pos = pos;
+	m->m_scrpos.ln = ln;
+	m->m_filename = NULL;
+}
 
 /*
  * Initialize the mark table to show no marks are set.
  */
 	public void
-init_mark()
+init_mark(VOID_PARAM)
 {
 	int i;
 
 	for (i = 0;  i < NMARKS;  i++)
-		marks[i].m_scrpos.pos = NULL_POSITION;
+	{
+		char letter;
+		switch (i) {
+		case MOUSEMARK: letter = '#'; break;
+		case LASTMARK: letter = '\''; break;
+		default: letter = (i < 26) ? 'a'+i : 'A'+i-26; break;
+		}
+		marks[i].m_letter = letter;
+		cmark(&marks[i], NULL_IFILE, NULL_POSITION, -1);
+	}
 }
 
 /*
- * See if a mark letter is valid (between a and z).
+ * Set m_ifile and clear m_filename.
+ */
+	static void
+mark_set_ifile(m, ifile)
+	struct mark *m;
+	IFILE ifile;
+{
+	m->m_ifile = ifile;
+	/* With m_ifile set, m_filename is no longer needed. */
+	free(m->m_filename);
+	m->m_filename = NULL;
+}
+
+/*
+ * Populate the m_ifile member of a mark struct from m_filename.
+ */
+	static void
+mark_get_ifile(m)
+	struct mark *m;
+{
+	if (m->m_ifile != NULL_IFILE)
+		return; /* m_ifile is already set */
+	mark_set_ifile(m, get_ifile(m->m_filename, prev_ifile(NULL_IFILE)));
+}
+
+/*
+ * Return the user mark struct identified by a character.
  */
 	static struct mark *
 getumark(c)
@@ -45,17 +118,17 @@ getumark(c)
 {
 	if (c >= 'a' && c <= 'z')
 		return (&marks[c-'a']);
-
 	if (c >= 'A' && c <= 'Z')
 		return (&marks[c-'A'+26]);
-
+	if (c == '#')
+		return (&marks[MOUSEMARK]);
 	error("Invalid mark letter", NULL_PARG);
 	return (NULL);
 }
 
 /*
  * Get the mark structure identified by a character.
- * The mark struct may come either from the mark table
+ * The mark struct may either be in the mark table (user mark)
  * or may be constructed on the fly for certain characters like ^, $.
  */
 	static struct mark *
@@ -72,9 +145,7 @@ getmark(c)
 		 * Beginning of the current file.
 		 */
 		m = &sm;
-		m->m_scrpos.pos = ch_zero();
-		m->m_scrpos.ln = 0;
-		m->m_ifile = curr_ifile;
+		cmark(m, curr_ifile, ch_zero(), 0);
 		break;
 	case '$':
 		/*
@@ -86,9 +157,7 @@ getmark(c)
 			return (NULL);
 		}
 		m = &sm;
-		m->m_scrpos.pos = ch_tell();
-		m->m_scrpos.ln = sc_height;
-		m->m_ifile = curr_ifile;
+		cmark(m, curr_ifile, ch_tell(), sc_height);
 		break;
 	case '.':
 		/*
@@ -96,7 +165,7 @@ getmark(c)
 		 */
 		m = &sm;
 		get_scrpos(&m->m_scrpos, TOP);
-		m->m_ifile = curr_ifile;
+		cmark(m, curr_ifile, m->m_scrpos.pos, m->m_scrpos.ln);
 		break;
 	case '\'':
 		/*
@@ -122,7 +191,7 @@ getmark(c)
 }
 
 /*
- * Is a mark letter is invalid?
+ * Is a mark letter invalid?
  */
 	public int
 badmark(c)
@@ -146,8 +215,13 @@ setmark(c, where)
 	if (m == NULL)
 		return;
 	get_scrpos(&scrpos, where);
-	m->m_scrpos = scrpos;
-	m->m_ifile = curr_ifile;
+	if (scrpos.pos == NULL_POSITION)
+	{
+		bell();
+		return;
+	}
+	cmark(m, curr_ifile, scrpos.pos, scrpos.ln);
+	marks_modified = 1;
 }
 
 /*
@@ -162,14 +236,20 @@ clrmark(c)
 	m = getumark(c);
 	if (m == NULL)
 		return;
+	if (m->m_scrpos.pos == NULL_POSITION)
+	{
+		bell();
+		return;
+	}
 	m->m_scrpos.pos = NULL_POSITION;
+	marks_modified = 1;
 }
 
 /*
  * Set lmark (the mark named by the apostrophe).
  */
 	public void
-lastmark()
+lastmark(VOID_PARAM)
 {
 	struct scrpos scrpos;
 
@@ -178,8 +258,7 @@ lastmark()
 	get_scrpos(&scrpos, TOP);
 	if (scrpos.pos == NULL_POSITION)
 		return;
-	marks[LASTMARK].m_scrpos = scrpos;
-	marks[LASTMARK].m_ifile = curr_ifile;
+	cmark(&marks[LASTMARK], curr_ifile, scrpos.pos, scrpos.ln);
 }
 
 /*
@@ -200,19 +279,14 @@ gomark(c)
 	 * If we're trying to go to the lastmark and 
 	 * it has not been set to anything yet,
 	 * set it to the beginning of the current file.
+	 * {{ Couldn't we instead set marks[LASTMARK] in edit()? }}
 	 */
 	if (m == &marks[LASTMARK] && m->m_scrpos.pos == NULL_POSITION)
-	{
-		m->m_ifile = curr_ifile;
-		m->m_scrpos.pos = ch_zero();
-		m->m_scrpos.ln = jump_sline;
-	}
+		cmark(m, curr_ifile, ch_zero(), jump_sline);
 
-	/*
-	 * If we're using lmark, we must save the screen position now,
-	 * because if we call edit_ifile() below, lmark will change.
-	 * (We save the screen position even if we're not using lmark.)
-	 */
+	mark_get_ifile(m);
+
+	/* Save scrpos; if it's LASTMARK it could change in edit_ifile. */
 	scrpos = m->m_scrpos;
 	if (m->m_ifile != curr_ifile)
 	{
@@ -260,13 +334,14 @@ posmark(pos)
 {
 	int i;
 
-	/* Only lower case and upper case letters */
-	for (i = 0;  i < 26*2;  i++)
+	/* Only user marks */
+	for (i = 0;  i < NUMARKS;  i++)
 	{
 		if (marks[i].m_ifile == curr_ifile && marks[i].m_scrpos.pos == pos)
 		{
 			if (i < 26) return 'a' + i;
-			return 'A' + i - 26;
+			if (i < 26*2) return 'A' + (i - 26);
+			return '#';
 		}
 	}
 	return 0;
@@ -285,3 +360,97 @@ unmark(ifile)
 		if (marks[i].m_ifile == ifile)
 			marks[i].m_scrpos.pos = NULL_POSITION;
 }
+
+/*
+ * Check if any marks refer to a specified ifile vi m_filename
+ * rather than m_ifile.
+ */
+	public void
+mark_check_ifile(ifile)
+	IFILE ifile;
+{
+	int i;
+	char *filename = lrealpath(get_filename(ifile));
+
+	for (i = 0;  i < NMARKS;  i++)
+	{
+		struct mark *m = &marks[i];
+		char *mark_filename = m->m_filename;
+		if (mark_filename != NULL)
+		{
+			mark_filename = lrealpath(mark_filename);
+			if (strcmp(filename, mark_filename) == 0)
+				mark_set_ifile(m, ifile);
+			free(mark_filename);
+		}
+	}
+	free(filename);
+}
+
+#if CMD_HISTORY
+
+/*
+ * Save marks to history file.
+ */
+	public void
+save_marks(fout, hdr)
+	FILE *fout;
+	char *hdr;
+{
+	int i;
+
+	if (!perma_marks)
+		return;
+
+	fprintf(fout, "%s\n", hdr);
+	for (i = 0;  i < NUMARKS;  i++)
+	{
+		char *filename;
+		struct mark *m = &marks[i];
+		char pos_str[INT_STRLEN_BOUND(m->m_scrpos.pos) + 2];
+		if (m->m_scrpos.pos == NULL_POSITION)
+			continue;
+		postoa(m->m_scrpos.pos, pos_str);
+		filename = m->m_filename;
+		if (filename == NULL)
+			filename = get_filename(m->m_ifile);
+		filename = lrealpath(filename);
+		if (strcmp(filename, "-") != 0)
+			fprintf(fout, "m %c %d %s %s\n",
+				m->m_letter, m->m_scrpos.ln, pos_str, filename);
+		free(filename);
+	}
+}
+
+/*
+ * Restore one mark from the history file.
+ */
+	public void
+restore_mark(line)
+	char *line;
+{
+	struct mark *m;
+	int ln;
+	POSITION pos;
+
+#define skip_whitespace while (*line == ' ') line++
+	if (*line++ != 'm')
+		return;
+	skip_whitespace;
+	m = getumark(*line++);
+	if (m == NULL)
+		return;
+	skip_whitespace;
+	ln = lstrtoi(line, &line);
+	if (ln < 1)
+		ln = 1;
+	if (ln > sc_height)
+		ln = sc_height;
+	skip_whitespace;
+	pos = lstrtopos(line, &line);
+	skip_whitespace;
+	cmark(m, NULL_IFILE, pos, ln);
+	m->m_filename = save(line);
+}
+
+#endif /* CMD_HISTORY */
diff --git a/mkutable b/mkutable
index 276062876bc9..b7c3e68285e9 100755
--- a/mkutable
+++ b/mkutable
@@ -4,7 +4,7 @@ use strict;
 my $USAGE = <<__EOF__;
    usage: mkutable [-n] [-f#] type... [--] [<] UnicodeData.txt
           -n = take non-matching types
-      -f = zero-based type field (default 2)
+          -f = zero-based type field (default 2)
 __EOF__
 
 use vars qw( $opt_f $opt_n );
diff --git a/optfunc.c b/optfunc.c
index 9185c011b108..7fe947ed9495 100644
--- a/optfunc.c
+++ b/optfunc.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -50,8 +50,10 @@ extern int jump_sline;
 extern long jump_sline_fraction;
 extern int shift_count;
 extern long shift_count_fraction;
-extern LWCHAR rscroll_char;
+extern char rscroll_char;
 extern int rscroll_attr;
+extern int mousecap;
+extern int wheel_lines;
 extern int less_is_more;
 #if LOGFILE
 extern char *namelogfile;
@@ -203,7 +205,7 @@ opt_j(type, s)
 }
 
 	public void
-calc_jump_sline()
+calc_jump_sline(VOID_PARAM)
 {
 	if (jump_sline_fraction < 0)
 		return;
@@ -267,7 +269,7 @@ opt_shift(type, s)
 	}
 }
 	public void
-calc_shift_count()
+calc_shift_count(VOID_PARAM)
 {
 	if (shift_count_fraction < 0)
 		return;
@@ -509,33 +511,13 @@ opt__V(type, s)
 		putstr("less ");
 		putstr(version);
 		putstr(" (");
-#if HAVE_GNU_REGEX
-		putstr("GNU ");
-#endif
-#if HAVE_POSIX_REGCOMP
-		putstr("POSIX ");
-#endif
-#if HAVE_PCRE
-		putstr("PCRE ");
-#endif
-#if HAVE_RE_COMP
-		putstr("BSD ");
-#endif
-#if HAVE_REGCMP
-		putstr("V8 ");
-#endif
-#if HAVE_V8_REGCOMP
-		putstr("Spencer V8 ");
-#endif
-#if !HAVE_GNU_REGEX && !HAVE_POSIX_REGCOMP && !HAVE_PCRE && !HAVE_RE_COMP && !HAVE_REGCMP && !HAVE_V8_REGCOMP
-		putstr("no ");
-#endif
-		putstr("regular expressions)\n");
-		putstr("Copyright (C) 1984-2017  Mark Nudelman\n\n");
+		putstr(pattern_lib_name());
+		putstr(" regular expressions)\n");
+		putstr("Copyright (C) 1984-2019  Mark Nudelman\n\n");
 		putstr("less comes with NO WARRANTY, to the extent permitted by law.\n");
 		putstr("For information about the terms of redistribution,\n");
 		putstr("see the file named README in the less distribution.\n");
-		putstr("Homepage: http://www.greenwoodsoftware.com/less\n");
+		putstr("Home page: http://www.greenwoodsoftware.com/less\n");
 		quit(QUIT_OK);
 		break;
 	}
@@ -809,10 +791,54 @@ opt_query(type, s)
 }
 
 /*
+ * Handler for the --mouse option.
+ */
+	/*ARGSUSED*/
+	public void
+opt_mousecap(type, s)
+	int type;
+	char *s;
+{
+	switch (type)
+	{
+	case TOGGLE:
+		if (mousecap == OPT_OFF)
+			deinit_mouse();
+		else
+			init_mouse();
+		break;
+	case INIT:
+	case QUERY:
+		break;
+	}
+}
+
+/*
+ * Handler for the --wheel-lines option.
+ */
+	/*ARGSUSED*/
+	public void
+opt_wheel_lines(type, s)
+	int type;
+	char *s;
+{
+	switch (type)
+	{
+	case INIT:
+	case TOGGLE:
+		if (wheel_lines <= 0)
+			wheel_lines = default_wheel_lines();
+		break;
+	case QUERY:
+		break;
+	}
+}
+
+/*
  * Get the "screen window" size.
  */
 	public int
-get_swindow()
+get_swindow(VOID_PARAM)
 {
 	if (swindow > 0)
 		return (swindow);
diff --git a/option.c b/option.c
index 8ba67bce3187..d402e11752c1 100644
--- a/option.c
+++ b/option.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -150,8 +150,11 @@ scan_option(s)
 			if (s == NULL)
 				return;
 			if (*str == '+')
+			{
+				if (every_first_cmd != NULL)
+					free(every_first_cmd);
 				every_first_cmd = save(str+1);
-			else
+			} else
 			{
 				ungetcc(CHAR_END_COMMAND);
 				ungetsc(str);
@@ -530,7 +533,7 @@ opt_prompt(o)
  * the previous option.
  */
 	public int
-isoptpending()
+isoptpending(VOID_PARAM)
 {
 	return (pendopt != NULL);
 }
@@ -551,7 +554,7 @@ nostring(printopt)
  * Print error message if a STRING type option is not followed by a string.
  */
 	public void
-nopendopt()
+nopendopt(VOID_PARAM)
 {
 	nostring(opt_desc(pendopt));
 }
@@ -699,7 +702,7 @@ getfraction(sp, printopt, errp)
  * Get the value of the -e flag.
  */
 	public int
-get_quit_at_eof()
+get_quit_at_eof(VOID_PARAM)
 {
 	if (!less_is_more)
 		return quit_at_eof;
diff --git a/option.h b/option.h
index b253da86f102..fb73416d387e 100644
--- a/option.h
+++ b/option.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
diff --git a/opttbl.c b/opttbl.c
index 0c68ccc3cd0f..967761cbc062 100644
--- a/opttbl.c
+++ b/opttbl.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -53,8 +53,12 @@ public int quit_on_intr;	/* Quit on interrupt */
 public int follow_mode;		/* F cmd Follows file desc or file name? */
 public int oldbot;		/* Old bottom of screen behavior {{REMOVE}} */
 public int opt_use_backslash;	/* Use backslash escaping in option parsing */
-public LWCHAR rscroll_char;	/* Char which marks chopped lines with -S */
+public char rscroll_char;	/* Char which marks chopped lines with -S */
 public int rscroll_attr;	/* Attribute of rscroll_char */
+public int no_hist_dups;	/* Remove dups from history list */
+public int mousecap;		/* Allow mouse for scrolling */
+public int wheel_lines;		/* Number of lines to scroll on mouse wheel scroll */
+public int perma_marks;		/* Save marks in history file */
 #if HILITE_SEARCH
 public int hilite_search;	/* Highlight matched search patterns? */
 #endif
@@ -120,6 +124,10 @@ static struct optname oldbot_optname = { "old-bot",              NULL };
 static struct optname follow_optname = { "follow-name",          NULL };
 static struct optname use_backslash_optname = { "use-backslash", NULL };
 static struct optname rscroll_optname = { "rscroll", NULL };
+static struct optname nohistdups_optname = { "no-histdups",      NULL };
+static struct optname mousecap_optname = { "mouse",              NULL };
+static struct optname wheel_lines_optname = { "wheel-lines",     NULL };
+static struct optname perma_marks_optname = { "save-marks",     NULL };
 
 
 /*
@@ -463,6 +471,38 @@ static struct loption option[] =
 		STRING|REPAINT|INIT_HANDLER, 0, NULL, opt_rscroll,
 		{ "right scroll character: ", NULL, NULL }
 	},
+	{ OLETTER_NONE, &nohistdups_optname,
+		BOOL, OPT_OFF, &no_hist_dups, NULL,
+		{
+			"Allow duplicates in history list",
+			"Remove duplicates from history list",
+			NULL
+		}
+	},
+	{ OLETTER_NONE, &mousecap_optname,
+		TRIPLE, OPT_OFF, &mousecap, opt_mousecap,
+		{
+			"Ignore mouse input",
+			"Use the mouse for scrolling",
+			"Use the mouse for scrolling (reverse)"
+		}
+	},
+	{ OLETTER_NONE, &wheel_lines_optname,
+		NUMBER|INIT_HANDLER, 0, &wheel_lines, opt_wheel_lines,
+		{
+			"Lines to scroll on mouse wheel: ",
+			"Scroll %d line(s) on mouse wheel",
+			NULL
+		}
+	},
+	{ OLETTER_NONE, &perma_marks_optname,
+		BOOL, OPT_OFF, &perma_marks, NULL,
+		{
+			"Don't save marks in history file",
+			"Save marks in history file",
+			NULL
+		}
+	},
 	{ '\0', NULL, NOVAR, 0, NULL, NULL, { NULL, NULL, NULL } }
 };
 
@@ -471,13 +511,13 @@ static struct loption option[] =
  * Initialize each option to its default value.
  */
 	public void
-init_option()
+init_option(VOID_PARAM)
 {
 	struct loption *o;
 	char *p;
 
 	p = lgetenv("LESS_IS_MORE");
-	if (p != NULL && *p != '\0')
+	if (!isnullenv(p))
 		less_is_more = 1;
 
 	for (o = option;  o->oletter != '\0';  o++)
diff --git a/os.c b/os.c
index df117610d82f..53c82e42e7f3 100644
--- a/os.c
+++ b/os.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -176,7 +176,7 @@ start:
  * Interrupt a pending iread().
  */
 	public void
-intread()
+intread(VOID_PARAM)
 {
 	LONG_JUMP(read_label, 1);
 }
@@ -186,7 +186,7 @@ intread()
  */
 #if HAVE_TIME
 	public time_type
-get_time()
+get_time(VOID_PARAM)
 {
 	time_type t;
 
diff --git a/output.c b/output.c
index c6a998120555..0563cf0b1713 100644
--- a/output.c
+++ b/output.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -50,7 +50,7 @@ extern int have_ul;
  * Display the line which is in the line buffer.
  */
 	public void
-put_line()
+put_line(VOID_PARAM)
 {
 	int c;
 	int i;
@@ -100,7 +100,7 @@ static char *ob = obuf;
  * overwritten or scrolled away.
  */
 	public void
-flush()
+flush(VOID_PARAM)
 {
 	int n;
 	int fd;
@@ -483,6 +483,27 @@ TYPE_TO_A_FUNC(linenumtoa, LINENUM)
 TYPE_TO_A_FUNC(inttoa, int)
 
 /*
+ * Convert an string to an integral type.
+ */
+#define STR_TO_TYPE_FUNC(funcname, type) \
+type funcname(buf, ebuf) \
+	char *buf; \
+	char **ebuf; \
+{ \
+	type val = 0; \
+	for (;;) { \
+		char c = *buf++; \
+		if (c < '0' || c > '9') break; \
+		val = 10 * val + c - '0'; \
+	} \
+	if (ebuf != NULL) *ebuf = buf; \
+	return val; \
+}
+
+STR_TO_TYPE_FUNC(lstrtopos, POSITION);
+STR_TO_TYPE_FUNC(lstrtoi, int);
+
+/*
  * Output an integer in a given radix.
  */
 	static int
@@ -566,7 +587,7 @@ less_printf(fmt, parg)
  * become the next command.
  */
 	public void
-get_return()
+get_return(VOID_PARAM)
 {
 	int c;
 
diff --git a/pattern.c b/pattern.c
index 563bde0cc697..da27dc647adc 100644
--- a/pattern.c
+++ b/pattern.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -14,6 +14,7 @@
 #include "less.h"
 
 extern int caseless;
+extern int utf_mode;
 
 /*
  * Compile a search pattern, for future use by match_pattern.
@@ -63,11 +64,11 @@ compile_pattern2(pattern, search_type, comp_pattern, show_error)
 	*comp_pattern = comp;
 #endif
 #if HAVE_PCRE
-	pcre *comp;
 	constant char *errstring;
 	int erroffset;
 	PARG parg;
-	comp = pcre_compile(pattern, 0,
+	pcre *comp = pcre_compile(pattern,
+			(utf_mode) ? PCRE_UTF8 | PCRE_NO_UTF8_CHECK : 0,
 			&errstring, &erroffset, NULL);
 	if (comp == NULL)
 	{
@@ -78,6 +79,25 @@ compile_pattern2(pattern, search_type, comp_pattern, show_error)
 	}
 	*comp_pattern = comp;
 #endif
+#if HAVE_PCRE2
+	int errcode;
+	PCRE2_SIZE erroffset;
+	PARG parg;
+	pcre2_code *comp = pcre2_compile((PCRE2_SPTR)pattern, strlen(pattern),
+			0, &errcode, &erroffset, NULL);
+	if (comp == NULL)
+	{
+		if (show_error)
+		{
+			char msg[160];
+			pcre2_get_error_message(errcode, (PCRE2_UCHAR*)msg, sizeof(msg));
+			parg.p_string = msg;
+			error("%s", &parg);
+		}
+		return (-1);
+	}
+	*comp_pattern = comp;
+#endif
 #if HAVE_RE_COMP
 	PARG parg;
 	if ((parg.p_string = re_comp(pattern)) != NULL)
@@ -174,6 +194,11 @@ uncompile_pattern(pattern)
 		pcre_free(*pattern);
 	*pattern = NULL;
 #endif
+#if HAVE_PCRE2
+	if (*pattern != NULL)
+		pcre2_code_free(*pattern);
+	*pattern = NULL;
+#endif
 #if HAVE_RE_COMP
 	*pattern = 0;
 #endif
@@ -223,6 +248,9 @@ is_null_pattern(pattern)
 #if HAVE_PCRE
 	return (pattern == NULL);
 #endif
+#if HAVE_PCRE2
+	return (pattern == NULL);
+#endif
 #if HAVE_RE_COMP
 	return (pattern == 0);
 #endif
@@ -351,6 +379,21 @@ match_pattern(pattern, tpattern, line, line_len, sp, ep, notbol, search_type)
 		}
 	}
 #endif
+#if HAVE_PCRE2
+	{
+		int flags = (notbol) ? PCRE2_NOTBOL : 0;
+		pcre2_match_data *md = pcre2_match_data_create(3, NULL);
+		matched = pcre2_match(pattern, (PCRE2_SPTR)line, line_len,
+			0, flags, md, NULL) >= 0;
+		if (matched)
+		{
+			PCRE2_SIZE *ovector = pcre2_get_ovector_pointer(md);
+			*sp = line + ovector[0];
+			*ep = line + ovector[1];
+		}
+		pcre2_match_data_free(md);
+	}
+#endif
 #if HAVE_RE_COMP
 	matched = (re_exec(line) == 1);
 	/*
@@ -382,3 +425,39 @@ match_pattern(pattern, tpattern, line, line_len, sp, ep, notbol, search_type)
 	return (matched);
 }
 
+/*
+ * Return the name of the pattern matching library.
+ */
+	public char *
+pattern_lib_name(VOID_PARAM)
+{
+#if HAVE_GNU_REGEX
+	return ("GNU");
+#else
+#if HAVE_POSIX_REGCOMP
+	return ("POSIX");
+#else
+#if HAVE_PCRE2
+	return ("PCRE2");
+#else
+#if HAVE_PCRE
+	return ("PCRE");
+#else
+#if HAVE_RE_COMP
+	return ("BSD");
+#else
+#if HAVE_REGCMP
+	return ("V8");
+#else
+#if HAVE_V8_REGCOMP
+	return ("Spencer V8");
+#else
+	return ("no");
+#endif
+#endif
+#endif
+#endif
+#endif
+#endif
+#endif
+}
diff --git a/pattern.h b/pattern.h
index 7bde5c7fa171..19ce5b9b6804 100644
--- a/pattern.h
+++ b/pattern.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -31,6 +31,13 @@
 #define CLEAR_PATTERN(name)   name = NULL
 #endif
 
+#if HAVE_PCRE2
+#define PCRE2_CODE_UNIT_WIDTH 8
+#include <pcre2.h>
+#define PATTERN_TYPE          pcre2_code *
+#define CLEAR_PATTERN(name)   name = NULL
+#endif
+
 #if HAVE_RE_COMP
 char *re_comp LESSPARAMS ((char*));
 int re_exec LESSPARAMS ((char*));
diff --git a/pckeys.h b/pckeys.h
index e0d86e7bdf36..fb345f284183 100644
--- a/pckeys.h
+++ b/pckeys.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
diff --git a/position.c b/position.c
index ae3899c1e95e..8a65ed4128fe 100644
--- a/position.c
+++ b/position.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -22,7 +22,7 @@
 #include "position.h"
 
 static POSITION *table = NULL;	/* The position table */
-static int table_size;
+static int table_size = 0;
 
 extern int sc_width, sc_height;
 
@@ -92,7 +92,7 @@ add_back_pos(pos)
  * Initialize the position table, done whenever we clear the screen.
  */
 	public void
-pos_clear()
+pos_clear(VOID_PARAM)
 {
 	int i;
 
@@ -104,7 +104,7 @@ pos_clear()
  * Allocate or reallocate the position table.
  */
 	public void
-pos_init()
+pos_init(VOID_PARAM)
 {
 	struct scrpos scrpos;
 
@@ -150,7 +150,7 @@ onscreen(pos)
  * See if the entire screen is empty.
  */
 	public int
-empty_screen()
+empty_screen(VOID_PARAM)
 {
 	return (empty_lines(0, sc_height-1));
 }
@@ -187,8 +187,20 @@ get_scrpos(scrpos, where)
 
 	switch (where)
 	{
-	case TOP: i = 0; dir = +1; last = sc_height-2; break;
-	default:  i = sc_height-2; dir = -1; last = 0; break;
+	case TOP:
+		i = 0; dir = +1; last = sc_height-2;
+		break;
+	case BOTTOM: case BOTTOM_PLUS_ONE:
+		i = sc_height-2; dir = -1; last = 0;
+		break;
+	default:
+		i = where;
+		if (table[i] == NULL_POSITION) {
+			scrpos->pos = NULL_POSITION;
+			return;
+		}
+		/* Values of dir and last don't matter after this. */
+		break;
 	}
 
 	/*
diff --git a/position.h b/position.h
index 30678962ccc7..77216daf1c43 100644
--- a/position.h
+++ b/position.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
diff --git a/prompt.c b/prompt.c
index 3067d2bbe3c3..12413fb9f930 100644
--- a/prompt.c
+++ b/prompt.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -66,7 +66,7 @@ static char *mp;
  * Initialize the prompt prototype strings.
  */
 	public void
-init_prompt()
+init_prompt(VOID_PARAM)
 {
 	prproto[0] = save(s_proto);
 	prproto[1] = save(less_is_more ? more_proto : m_proto);
@@ -150,7 +150,7 @@ ap_int(num)
  * Append a question mark to the end of the message.
  */
 	static void
-ap_quest()
+ap_quest(VOID_PARAM)
 {
 	ap_str("?");
 }
@@ -196,10 +196,13 @@ cond(c, where)
 	case 'e':	/* At end of file? */
 		return (eof_displayed());
 	case 'f':	/* Filename known? */
+	case 'g':
 		return (strcmp(get_filename(curr_ifile), "-") != 0);
 	case 'l':	/* Line number known? */
 	case 'd':	/* Same as l */
-		return (linenums);
+		if (!linenums)
+			return 0;
+		return (currline(where) != 0);
 	case 'L':	/* Final line number known? */
 	case 'D':	/* Final page number known? */
 		return (linenums && ch_length() != NULL_POSITION);
@@ -254,6 +257,7 @@ protochar(c, where, iseditproto)
 	LINENUM linenum;
 	LINENUM last_linenum;
 	IFILE h;
+	char *s;
 
 #undef  PAGE_NUM
 #define PAGE_NUM(linenum)  ((((linenum) - 1) / (sc_height - 1)) + 1)
@@ -305,6 +309,11 @@ protochar(c, where, iseditproto)
 	case 'F':	/* Last component of file name */
 		ap_str(last_component(get_filename(curr_ifile)));
 		break;
+	case 'g':	/* Shell-escaped file name */
+		s = shell_quote(get_filename(curr_ifile));
+		ap_str(s);
+		free(s);
+		break;
 	case 'i':	/* Index into list of files */
 #if TAGS
 		if (ntags())
@@ -551,7 +560,7 @@ pr_expand(proto, maxwidth)
  * Return a message suitable for printing by the "=" command.
  */
 	public char *
-eq_message()
+eq_message(VOID_PARAM)
 {
 	return (pr_expand(eqproto, 0));
 }
@@ -563,7 +572,7 @@ eq_message()
  * and the caller will prompt with a colon.
  */
 	public char *
-pr_string()
+pr_string(VOID_PARAM)
 {
 	char *prompt;
 	int type;
@@ -580,7 +589,7 @@ pr_string()
  * Return a message suitable for printing while waiting in the F command.
  */
 	public char *
-wait_message()
+wait_message(VOID_PARAM)
 {
 	return (pr_expand(wproto, sc_width-so_s_width-so_e_width-2));
 }
diff --git a/screen.c b/screen.c
index dfee5d217040..cd25d744e897 100644
--- a/screen.c
+++ b/screen.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -120,7 +120,8 @@ struct keyRecord
 static int keyCount = 0;
 static WORD curr_attr;
 static int pending_scancode = 0;
-static WORD *whitescreen;
+static char x11mousebuf[] = "[M???";    /* Mouse report, after ESC */
+static int x11mousePos, x11mouseCount;
 
 static HANDLE con_out_save = INVALID_HANDLE_VALUE; /* previous console */
 static HANDLE con_out_ours = INVALID_HANDLE_VALUE; /* our own */
@@ -187,6 +188,8 @@ static char
 	*sc_backspace,		/* Backspace cursor */
 	*sc_s_keypad,		/* Start keypad mode */
 	*sc_e_keypad,		/* End keypad mode */
+	*sc_s_mousecap,		/* Start mouse capture mode */
+	*sc_e_mousecap,		/* End mouse capture mode */
 	*sc_init,		/* Startup terminal initialization */
 	*sc_deinit;		/* Exit terminal de-initialization */
 #endif
@@ -211,8 +214,9 @@ public int missing_cap = 0;	/* Some capability is missing */
 public char *kent = NULL;	/* Keypad ENTER sequence */
 
 static int attrmode = AT_NORMAL;
+static int termcap_debug = -1;
 extern int binattr;
-extern int line_count;
+extern int one_screen;
 
 #if !MSDOS_COMPILER
 static char *cheaper();
@@ -240,13 +244,18 @@ extern int no_keypad;
 extern int sigs;
 extern int wscroll;
 extern int screen_trashed;
-extern int tty;
 extern int top_scroll;
 extern int quit_if_one_screen;
 extern int oldbot;
+extern int mousecap;
 #if HILITE_SEARCH
 extern int hilite_search;
 #endif
+#if MSDOS_COMPILER==WIN32C
+extern HANDLE tty;
+#else
+extern int tty;
+#endif
 
 extern char *tgetstr();
 extern char *tgoto();
@@ -632,11 +641,10 @@ static int hardcopy;
 ltget_env(capname)
 	char *capname;
 {
-	char name[16];
+	char name[64];
 	char *s;
 
-	s = lgetenv("LESS_TERMCAP_DEBUG");
-	if (s != NULL && *s != '\0')
+	if (termcap_debug)
 	{
 		struct env { struct env *next; char *name; char *value; };
 		static struct env *envs = NULL;
@@ -652,8 +660,7 @@ ltget_env(capname)
 		envs = p;
 		return p->value;
 	}
-	strcpy(name, "LESS_TERMCAP_");
-	strcat(name, capname);
+	SNPRINTF1(name, sizeof(name), "LESS_TERMCAP_%s", capname);
 	return (lgetenv(name));
 }
 
@@ -702,7 +709,7 @@ ltgetstr(capname, pp)
  * Get size of the output screen.
  */
 	public void
-scrsize()
+scrsize(VOID_PARAM)
 {
 	char *s;
 	int sys_height;
@@ -832,7 +839,7 @@ scrsize()
  * Figure out how many empty loops it takes to delay a millisecond.
  */
 	static void
-get_clock()
+get_clock(VOID_PARAM)
 {
 	clock_t start;
 	
@@ -860,13 +867,6 @@ get_clock()
  * Delay for a specified number of milliseconds.
  */
 	static void
-dummy_func()
-{
-	static long delay_dummy = 0;
-	delay_dummy++;
-}
-
-	static void
 delay(msec)
 	int msec;
 {
@@ -875,13 +875,7 @@ delay(msec)
 	while (msec-- > 0)
 	{
 		for (i = 0;  i < msec_loops;  i++)
-		{
-			/*
-			 * Make it look like we're doing something here,
-			 * so the optimizer doesn't remove the whole loop.
-			 */
-			dummy_func();
-		}
+			(void) clock();
 	}
 }
 #endif
@@ -949,17 +943,13 @@ special_key_str(key)
 		s = windowid ? ltgetstr("@7", &sp) : k_end;
 		break;
 	case SK_DELETE:
-		if (windowid)
+		s = windowid ? ltgetstr("kD", &sp) : k_delete;
+		if (s == NULL)
 		{
-			s = ltgetstr("kD", &sp);
-			if (s == NULL)
-			{
-				tbuf[0] = '\177';
-				tbuf[1] = '\0';
-				s = tbuf;
-			}
-		} else
-			s = k_delete;
+			tbuf[0] = '\177';
+			tbuf[1] = '\0';
+			s = tbuf;
+		}
 		break;
 #endif
 #if MSDOS_COMPILER
@@ -1063,8 +1053,9 @@ special_key_str(key)
  * Get terminal capabilities via termcap.
  */
 	public void
-get_term()
+get_term(VOID_PARAM)
 {
+	termcap_debug = !isnullenv(lgetenv("LESS_TERMCAP_DEBUG"));
 #if MSDOS_COMPILER
 	auto_wrap = 1;
 	ignaw = 0;
@@ -1127,7 +1118,7 @@ get_term()
 
 
 #else /* !MSDOS_COMPILER */
-
+{
 	char *sp;
 	char *t1, *t2;
 	char *term;
@@ -1140,7 +1131,7 @@ get_term()
 	 * Make sure the termcap database is available.
 	 */
 	sp = lgetenv("TERMCAP");
-	if (sp == NULL || *sp == '\0')
+	if (isnullenv(sp))
 	{
 		char *termcap;
 		if ((sp = homefile("termcap.dat")) != NULL)
@@ -1220,6 +1211,13 @@ get_term()
 		sc_e_keypad = "";
 	kent = ltgetstr("@8", &sp);
 
+	sc_s_mousecap = ltgetstr("MOUSE_START", &sp);
+	if (sc_s_mousecap == NULL)
+		sc_s_mousecap = ESCS "[?1000h" ESCS "[?1006h";
+	sc_e_mousecap = ltgetstr("MOUSE_END", &sp);
+	if (sc_e_mousecap == NULL)
+		sc_e_mousecap = ESCS "[?1006l" ESCS "[?1000l";
+
 	sc_init = ltgetstr("ti", &sp);
 	if (sc_init == NULL)
 		sc_init = "";
@@ -1347,6 +1345,7 @@ get_term()
 		 */
 		no_back_scroll = 1;
 	}
+}
 #endif /* MSDOS_COMPILER */
 }
 
@@ -1459,7 +1458,7 @@ _settextposition(int row, int col)
  * Initialize the screen to the correct color at startup.
  */
 	static void
-initcolor()
+initcolor(VOID_PARAM)
 {
 #if MSDOS_COMPILER==BORLANDC || MSDOS_COMPILER==DJGPPC
 	intensevideo();
@@ -1495,7 +1494,7 @@ initcolor()
  * Termcap-like init with a private win32 console.
  */
 	static void
-win32_init_term()
+win32_init_term(VOID_PARAM)
 {
 	CONSOLE_SCREEN_BUFFER_INFO scr;
 	COORD size;
@@ -1537,8 +1536,8 @@ win32_init_term()
 /*
  * Restore the startup console.
  */
-static void
-win32_deinit_term()
+	static void
+win32_deinit_term(VOID_PARAM)
 {
 	if (con_out_save == INVALID_HANDLE_VALUE)
 		return;
@@ -1551,18 +1550,56 @@ win32_deinit_term()
 #endif
 
 /*
+ * Configure the termimal so mouse clicks and wheel moves 
+ * produce input to less.
+ */
+	public void
+init_mouse(VOID_PARAM)
+{
+	if (!mousecap)
+		return;
+#if !MSDOS_COMPILER
+	tputs(sc_s_mousecap, sc_height, putchr);
+#else
+#if MSDOS_COMPILER==WIN32C
+	SetConsoleMode(tty, ENABLE_PROCESSED_INPUT | ENABLE_MOUSE_INPUT);
+#endif
+#endif
+}
+
+/*
+ * Configure the terminal so mouse clicks and wheel moves
+ * are handled by the system (so text can be selected, etc).
+ */
+	public void
+deinit_mouse(VOID_PARAM)
+{
+	if (!mousecap)
+		return;
+#if !MSDOS_COMPILER
+	tputs(sc_e_mousecap, sc_height, putchr);
+#else
+#if MSDOS_COMPILER==WIN32C
+	SetConsoleMode(tty, ENABLE_PROCESSED_INPUT);
+#endif
+#endif
+}
+
+/*
  * Initialize terminal
  */
 	public void
-init()
+init(VOID_PARAM)
 {
 #if !MSDOS_COMPILER
-	if (quit_if_one_screen && line_count >= sc_height)
-		quit_if_one_screen = FALSE;
-	if (!no_init && !quit_if_one_screen)
-		tputs(sc_init, sc_height, putchr);
-	if (!no_keypad)
-		tputs(sc_s_keypad, sc_height, putchr);
+	if (!(quit_if_one_screen && one_screen))
+	{
+		if (!no_init)
+			tputs(sc_init, sc_height, putchr);
+		if (!no_keypad)
+			tputs(sc_s_keypad, sc_height, putchr);
+		init_mouse();
+	}
 	if (top_scroll) 
 	{
 		int i;
@@ -1592,15 +1629,19 @@ init()
  * Deinitialize terminal
  */
 	public void
-deinit()
+deinit(VOID_PARAM)
 {
 	if (!init_done)
 		return;
 #if !MSDOS_COMPILER
-	if (!no_keypad)
-		tputs(sc_e_keypad, sc_height, putchr);
-	if (!no_init && !quit_if_one_screen)
-		tputs(sc_deinit, sc_height, putchr);
+	if (!(quit_if_one_screen && one_screen))
+	{
+		deinit_mouse();
+		if (!no_keypad)
+			tputs(sc_e_keypad, sc_height, putchr);
+		if (!no_init)
+			tputs(sc_deinit, sc_height, putchr);
+	}
 #else
 	/* Restore system colors. */
 	SETCOLORS(sy_fg_color, sy_bg_color);
@@ -1619,7 +1660,7 @@ deinit()
  * Home cursor (move to upper left corner of screen).
  */
 	public void
-home()
+home(VOID_PARAM)
 {
 #if !MSDOS_COMPILER
 	tputs(sc_home, 1, putchr);
@@ -1634,7 +1675,7 @@ home()
  * Should scroll the display down.
  */
 	public void
-add_line()
+add_line(VOID_PARAM)
 {
 #if !MSDOS_COMPILER
 	tputs(sc_addline, sc_height, putchr);
@@ -1746,7 +1787,7 @@ remove_top(n)
  * Clear the screen.
  */
 	static void
-win32_clear()
+win32_clear(VOID_PARAM)
 {
 	/*
 	 * This will clear only the currently visible rows of the NT
@@ -1843,7 +1884,7 @@ win32_scroll_up(n)
  * Move cursor to lower left corner of screen.
  */
 	public void
-lower_left()
+lower_left(VOID_PARAM)
 {
 	if (!init_done)
 		return;
@@ -1859,7 +1900,7 @@ lower_left()
  * Move cursor to left position of current line.
  */
 	public void
-line_left()
+line_left(VOID_PARAM)
 {
 #if !MSDOS_COMPILER
 	tputs(sc_return, 1, putchr);
@@ -1891,7 +1932,7 @@ line_left()
  * (in lieu of SIGWINCH for WIN32).
  */
 	public void
-check_winch()
+check_winch(VOID_PARAM)
 {
 #if MSDOS_COMPILER==WIN32C
 	CONSOLE_SCREEN_BUFFER_INFO scr;
@@ -1940,7 +1981,7 @@ goto_line(sindex)
  * {{ Yuck!  There must be a better way to get a visual bell. }}
  */
 	static void
-create_flash()
+create_flash(VOID_PARAM)
 {
 #if MSDOS_COMPILER==MSOFTC
 	struct videoconfig w;
@@ -1977,18 +2018,6 @@ create_flash()
 		return;
 	for (n = 0;  n < sc_width * sc_height;  n++)
 		whitescreen[n] = 0x7020;
-#else
-#if MSDOS_COMPILER==WIN32C
-	int n;
-
-	whitescreen = (WORD *)
-		malloc(sc_height * sc_width * sizeof(WORD));
-	if (whitescreen == NULL)
-		return;
-	/* Invert the standard colors. */
-	for (n = 0;  n < sc_width * sc_height;  n++)
-		whitescreen[n] = (WORD)((nm_fg_color << 4) | nm_bg_color);
-#endif
 #endif
 #endif
 	flash_created = 1;
@@ -1999,7 +2028,7 @@ create_flash()
  * Output the "visual bell", if there is one.
  */
 	public void
-vbell()
+vbell(VOID_PARAM)
 {
 #if !MSDOS_COMPILER
 	if (*sc_visual_bell == '\0')
@@ -2063,7 +2092,7 @@ vbell()
  * Make a noise.
  */
 	static void
-beep()
+beep(VOID_PARAM)
 {
 #if !MSDOS_COMPILER
 	putchr(CONTROL('G'));
@@ -2080,7 +2109,7 @@ beep()
  * Ring the terminal bell.
  */
 	public void
-bell()
+bell(VOID_PARAM)
 {
 	if (quiet == VERY_QUIET)
 		vbell();
@@ -2092,7 +2121,7 @@ bell()
  * Clear the screen.
  */
 	public void
-clear()
+clear(VOID_PARAM)
 {
 #if !MSDOS_COMPILER
 	tputs(sc_clear, sc_height, putchr);
@@ -2111,7 +2140,7 @@ clear()
  * {{ This must not move the cursor. }}
  */
 	public void
-clear_eol()
+clear_eol(VOID_PARAM)
 {
 #if !MSDOS_COMPILER
 	tputs(sc_eol_clear, 1, putchr);
@@ -2170,7 +2199,7 @@ clear_eol()
  * Clear the screen if there's off-screen memory below the display.
  */
 	static void
-clear_eol_bot()
+clear_eol_bot(VOID_PARAM)
 {
 #if MSDOS_COMPILER
 	clear_eol();
@@ -2187,7 +2216,7 @@ clear_eol_bot()
  * Leave the cursor at the beginning of the bottom line.
  */
 	public void
-clear_bot()
+clear_bot(VOID_PARAM)
 {
 	/*
 	 * If we're in a non-normal attribute mode, temporarily exit
@@ -2251,7 +2280,7 @@ at_enter(attr)
 }
 
 	public void
-at_exit()
+at_exit(VOID_PARAM)
 {
 #if !MSDOS_COMPILER
 	/* Undo things in the reverse order we did them.  */
@@ -2315,7 +2344,7 @@ apply_at_specials(attr)
  * and move the cursor left.
  */
 	public void
-backspace()
+backspace(VOID_PARAM)
 {
 #if !MSDOS_COMPILER
 	/* 
@@ -2364,8 +2393,12 @@ backspace()
  * Output a plain backspace, without erasing the previous char.
  */
 	public void
-putbs()
+putbs(VOID_PARAM)
 {
+	if (termcap_debug)
+		putstr("<bs>");
+	else
+	{
 #if !MSDOS_COMPILER
 	tputs(sc_backspace, 1, putchr);
 #else
@@ -2396,15 +2429,15 @@ putbs()
 		return;
 	_settextposition(row, col-1);
 #endif /* MSDOS_COMPILER */
+	}
 }
 
 #if MSDOS_COMPILER==WIN32C
 /*
  * Determine whether an input character is waiting to be read.
  */
-	static int
-win32_kbhit(tty)
-	HANDLE tty;
+	public int
+win32_kbhit(VOID_PARAM)
 {
 	INPUT_RECORD ip;
 	DWORD read;
@@ -2415,6 +2448,14 @@ win32_kbhit(tty)
 	currentKey.ascii = 0;
 	currentKey.scan = 0;
 
+	if (x11mouseCount > 0)
+	{
+		currentKey.ascii = x11mousebuf[x11mousePos++];
+		--x11mouseCount;
+		keyCount = 1;
+		return (TRUE);
+	}
+
 	/*
 	 * Wait for a real key-down event, but
 	 * ignore SHIFT and CONTROL key events.
@@ -2425,6 +2466,34 @@ win32_kbhit(tty)
 		if (read == 0)
 			return (FALSE);
 		ReadConsoleInput(tty, &ip, 1, &read);
+		/* generate an X11 mouse sequence from the mouse event */
+		if (mousecap && ip.EventType == MOUSE_EVENT &&
+		    ip.Event.MouseEvent.dwEventFlags != MOUSE_MOVED)
+		{
+			x11mousebuf[3] = X11MOUSE_OFFSET + ip.Event.MouseEvent.dwMousePosition.X + 1;
+			x11mousebuf[4] = X11MOUSE_OFFSET + ip.Event.MouseEvent.dwMousePosition.Y + 1;
+			switch (ip.Event.MouseEvent.dwEventFlags)
+			{
+			case 0: /* press or release */
+				if (ip.Event.MouseEvent.dwButtonState == 0)
+					x11mousebuf[2] = X11MOUSE_OFFSET + X11MOUSE_BUTTON_REL;
+				else if (ip.Event.MouseEvent.dwButtonState & (FROM_LEFT_3RD_BUTTON_PRESSED | FROM_LEFT_4TH_BUTTON_PRESSED))
+					continue;
+				else
+					x11mousebuf[2] = X11MOUSE_OFFSET + X11MOUSE_BUTTON1 + ((int)ip.Event.MouseEvent.dwButtonState << 1);
+				break;
+			case MOUSE_WHEELED:
+				x11mousebuf[2] = X11MOUSE_OFFSET + (((int)ip.Event.MouseEvent.dwButtonState < 0) ? X11MOUSE_WHEEL_DOWN : X11MOUSE_WHEEL_UP);
+				break;
+			default:
+				continue;
+			}
+			x11mousePos = 0;
+			x11mouseCount = 5;
+			currentKey.ascii = ESC;
+			keyCount = 1;
+			return (TRUE);
+		}
 	} while (ip.EventType != KEY_EVENT ||
 		ip.Event.KeyEvent.bKeyDown != TRUE ||
 		ip.Event.KeyEvent.wVirtualScanCode == 0 ||
@@ -2477,8 +2546,7 @@ win32_kbhit(tty)
  * Read a character from the keyboard.
  */
 	public char
-WIN32getch(tty)
-	int tty;
+WIN32getch(VOID_PARAM)
 {
 	int ascii;
 
@@ -2488,21 +2556,25 @@ WIN32getch(tty)
 		return ((char)(currentKey.scan & 0x00FF));
 	}
 
-	while (win32_kbhit((HANDLE)tty) == FALSE)
-	{
-		Sleep(20);
-		if (ABORT_SIGS())
-			return ('\003');
-		continue;
-	}
-	keyCount --;
-	ascii = currentKey.ascii;
-	/*
-	 * On PC's, the extended keys return a 2 byte sequence beginning 
-	 * with '00', so if the ascii code is 00, the next byte will be 
-	 * the lsb of the scan code.
-	 */
-	pending_scancode = (ascii == 0x00);
+	do {
+		while (win32_kbhit() == FALSE)
+		{
+			Sleep(20);
+			if (ABORT_SIGS())
+				return ('\003');
+			continue;
+		}
+		keyCount --;
+		ascii = currentKey.ascii;
+		/*
+		 * On PC's, the extended keys return a 2 byte sequence beginning 
+		 * with '00', so if the ascii code is 00, the next byte will be 
+		 * the lsb of the scan code.
+		 */
+		pending_scancode = (ascii == 0x00);
+	} while (pending_scancode &&
+		(currentKey.scan == PCK_CAPS_LOCK || currentKey.scan == PCK_NUM_LOCK));
+
 	return ((char)ascii);
 }
 #endif
diff --git a/scrsize.c b/scrsize.c
index 001c55ace385..1e3be1fa71f1 100644
--- a/scrsize.c
+++ b/scrsize.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
diff --git a/search.c b/search.c
index 72191889af97..e1d007344513 100644
--- a/search.c
+++ b/search.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -204,7 +204,7 @@ init_pattern(info)
  * Initialize search variables.
  */
 	public void
-init_search()
+init_search(VOID_PARAM)
 {
 	init_pattern(&search_info);
 	init_pattern(&filter_info);
@@ -214,7 +214,7 @@ init_search()
  * Determine which text conversions to perform before pattern matching.
  */
 	static int
-get_cvt_ops()
+get_cvt_ops(VOID_PARAM)
 {
 	int ops = 0;
 	if (is_caseless || bs_mode == BS_SPECIAL)
@@ -297,7 +297,7 @@ repaint_hilite(on)
  * Clear the attn hilite.
  */
 	public void
-clear_attn()
+clear_attn(VOID_PARAM)
 {
 	int sindex;
 	POSITION old_start_attnpos;
@@ -344,7 +344,7 @@ clear_attn()
  * Hide search string highlighting.
  */
 	public void
-undo_search()
+undo_search(VOID_PARAM)
 {
 	if (!prev_pattern(&search_info))
 	{
@@ -389,13 +389,13 @@ clr_hlist(anchor)
 }
 
 	public void
-clr_hilite()
+clr_hilite(VOID_PARAM)
 {
 	clr_hlist(&hilite_anchor);
 }
 
 	public void
-clr_filter()
+clr_filter(VOID_PARAM)
 {
 	clr_hlist(&filter_anchor);
 }
@@ -1031,7 +1031,7 @@ hilite_line(linepos, line, line_len, chpos, sp, ep, cvt_ops)
  * Find matching text which is currently on screen and highlight it.
  */
 	static void
-hilite_screen()
+hilite_screen(VOID_PARAM)
 {
 	struct scrpos scrpos;
 
@@ -1046,7 +1046,7 @@ hilite_screen()
  * Change highlighting parameters.
  */
 	public void
-chg_hilite()
+chg_hilite(VOID_PARAM)
 {
 	/*
 	 * Erase any highlights currently on screen.
@@ -1377,7 +1377,7 @@ hist_pattern(search_type)
  * Updates the internal search state to reflect a change in the -i flag.
  */
 	public void
-chg_caseless()
+chg_caseless(VOID_PARAM)
 {
 	if (!is_ucase_pattern)
 		/*
@@ -1730,7 +1730,7 @@ set_filter_pattern(pattern, search_type)
  * Is there a line filter in effect?
  */
 	public int
-is_filtering()
+is_filtering(VOID_PARAM)
 {
 	if (ch_getflags() & CH_HELPFILE)
 		return (0);
diff --git a/signal.c b/signal.c
index f53b2f90e832..4f7444cab90b 100644
--- a/signal.c
+++ b/signal.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -38,6 +38,7 @@ extern long jump_sline_fraction;
 /*
  * Interrupt signal handler.
  */
+#if MSDOS_COMPILER!=WIN32C
 	/* ARGSUSED*/
 	static RETSIGTYPE
 u_interrupt(type)
@@ -61,6 +62,7 @@ u_interrupt(type)
 	if (reading)
 		intread(); /* May longjmp */
 }
+#endif
 
 #ifdef SIGTSTP
 /*
@@ -107,7 +109,8 @@ winch(type)
 /*
  * Handle CTRL-C and CTRL-BREAK keys.
  */
-#include "windows.h"
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
 
 	static BOOL WINAPI 
 wbreak_handler(dwCtrlType)
@@ -145,9 +148,10 @@ init_signals(on)
 		/*
 		 * Set signal handlers.
 		 */
-		(void) LSIGNAL(SIGINT, u_interrupt);
 #if MSDOS_COMPILER==WIN32C
 		SetConsoleCtrlHandler(wbreak_handler, TRUE);
+#else
+		(void) LSIGNAL(SIGINT, u_interrupt);
 #endif
 #ifdef SIGTSTP
 		(void) LSIGNAL(SIGTSTP, stop);
@@ -169,9 +173,10 @@ init_signals(on)
 		/*
 		 * Restore signals to defaults.
 		 */
-		(void) LSIGNAL(SIGINT, SIG_DFL);
 #if MSDOS_COMPILER==WIN32C
 		SetConsoleCtrlHandler(wbreak_handler, FALSE);
+#else
+		(void) LSIGNAL(SIGINT, SIG_DFL);
 #endif
 #ifdef SIGTSTP
 		(void) LSIGNAL(SIGTSTP, SIG_DFL);
@@ -196,7 +201,7 @@ init_signals(on)
  * A received signal cause a bit to be set in "sigs".
  */
 	public void
-psignals()
+psignals(VOID_PARAM)
 {
 	int tsignals;
 
@@ -250,8 +255,8 @@ psignals()
 			wscroll = (sc_height + 1) / 2;
 			calc_jump_sline();
 			calc_shift_count();
-			screen_trashed = 1;
 		}
+		screen_trashed = 1;
 	}
 #endif
 	if (tsignals & S_INTERRUPT)
diff --git a/tags.c b/tags.c
index ebb30488de1e..9a413b7ef2a1 100644
--- a/tags.c
+++ b/tags.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -38,7 +38,7 @@ enum tag_result {
 enum {
 	T_CTAGS,	/* 'tags': standard and extended format (ctags) */
 	T_CTAGS_X,	/* stdin: cross reference format (ctags) */
-	T_GTAGS,	/* 'GTAGS': function defenition (global) */
+	T_GTAGS,	/* 'GTAGS': function definition (global) */
 	T_GRTAGS,	/* 'GRTAGS': function reference (global) */
 	T_GSYMS,	/* 'GSYMS': other symbols (global) */
 	T_GPATH		/* 'GPATH': path name (global) */
@@ -89,7 +89,7 @@ static struct tag *curtag;
  * Delete tag structures.
  */
 	public void
-cleantags()
+cleantags(VOID_PARAM)
 {
 	struct tag *tp;
 
@@ -141,7 +141,7 @@ maketagent(name, file, linenum, pattern, endline)
  * Get tag mode.
  */
 	public int
-gettagtype()
+gettagtype(VOID_PARAM)
 {
 	int f;
 
@@ -203,7 +203,7 @@ findtag(tag)
  * Search for a tag.
  */
 	public POSITION
-tagsearch()
+tagsearch(VOID_PARAM)
 {
 	if (curtag == NULL)
 		return (NULL_POSITION);  /* No gtags loaded! */
@@ -245,7 +245,7 @@ prevtag(n)
  * Return the total number of tags.
  */
 	public int
-ntags()
+ntags(VOID_PARAM)
 {
 	return total;
 }
@@ -254,7 +254,7 @@ ntags()
  * Return the sequence number of current tag.
  */
 	public int
-curr_tag()
+curr_tag(VOID_PARAM)
 {
 	return curseq;
 }
@@ -380,7 +380,7 @@ findctag(tag)
  * Edit current tagged file.
  */
 	public int
-edit_tagfile()
+edit_tagfile(VOID_PARAM)
 {
 	if (curtag == NULL)
 		return (1);
@@ -417,7 +417,7 @@ curtag_match(char const *line, POSITION linepos)
  *	parentheses (which are almost always found in a tag).
  */
 	static POSITION
-ctagsearch()
+ctagsearch(VOID_PARAM)
 {
 	POSITION pos, linepos;
 	LINENUM linenum;
@@ -529,7 +529,7 @@ findgtag(tag, type)
 		char *qtag;
 		char *cmd = lgetenv("LESSGLOBALTAGS");
 
-		if (cmd == NULL || *cmd == '\0')
+		if (isnullenv(cmd))
 			return TAG_NOFILE;
 		/* Get suitable flag value for global(1). */
 		switch (type)
@@ -631,7 +631,7 @@ static int circular = 0;	/* 1: circular tag structure */
  * appropriate tag.
  */
 	static char *
-nextgtag()
+nextgtag(VOID_PARAM)
 {
 	struct tag *tp;
 
@@ -661,7 +661,7 @@ nextgtag()
  * at the appropriate tag.
  */
 	static char *
-prevgtag()
+prevgtag(VOID_PARAM)
 {
 	struct tag *tp;
 
@@ -691,7 +691,7 @@ prevgtag()
  * if it was unable to position at the tag, 0 if successful.
  */
 	static POSITION
-gtagsearch()
+gtagsearch(VOID_PARAM)
 {
 	if (curtag == NULL)
 		return (NULL_POSITION);  /* No gtags loaded! */
diff --git a/ttyin.c b/ttyin.c
index 87cffc28eb26..8ef11eff5930 100644
--- a/ttyin.c
+++ b/ttyin.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -18,20 +18,25 @@
 #include "pckeys.h"
 #endif
 #if MSDOS_COMPILER==WIN32C
-#include "windows.h"
-extern char WIN32getch();
-static DWORD console_mode;
+#define WIN32_LEAN_AND_MEAN
+#ifndef _WIN32_WINNT
+#define _WIN32_WINNT 0x400
 #endif
-
+#include <windows.h>
+static DWORD console_mode;
+public HANDLE tty;
+#else
 public int tty;
+#endif
 extern int sigs;
 extern int utf_mode;
+extern int wheel_lines;
 
 /*
  * Open keyboard for input.
  */
 	public void
-open_getchr()
+open_getchr(VOID_PARAM)
 {
 #if MSDOS_COMPILER==WIN32C
 	/* Need this to let child processes inherit our console handle */
@@ -39,12 +44,12 @@ open_getchr()
 	memset(&sa, 0, sizeof(SECURITY_ATTRIBUTES));
 	sa.nLength = sizeof(SECURITY_ATTRIBUTES);
 	sa.bInheritHandle = TRUE;
-	tty = (int) CreateFile("CONIN$", GENERIC_READ,
+	tty = CreateFile("CONIN$", GENERIC_READ | GENERIC_WRITE,
 			FILE_SHARE_READ, &sa, 
 			OPEN_EXISTING, 0L, NULL);
-	GetConsoleMode((HANDLE)tty, &console_mode);
+	GetConsoleMode(tty, &console_mode);
 	/* Make sure we get Ctrl+C events. */
-	SetConsoleMode((HANDLE)tty, ENABLE_PROCESSED_INPUT);
+	SetConsoleMode(tty, ENABLE_PROCESSED_INPUT | ENABLE_MOUSE_INPUT);
 #else
 #if MSDOS_COMPILER
 	extern int fd0;
@@ -85,19 +90,52 @@ open_getchr()
  * Close the keyboard.
  */
 	public void
-close_getchr()
+close_getchr(VOID_PARAM)
+{
+#if MSDOS_COMPILER==WIN32C
+	SetConsoleMode(tty, console_mode);
+	CloseHandle(tty);
+#endif
+}
+
+#if MSDOS_COMPILER==WIN32C
+/*
+ * Close the pipe, restoring the keyboard (CMD resets it, losing the mouse).
+ */
+	int
+pclose(f)
+	FILE *f;
+{
+	int result;
+
+	result = _pclose(f);
+	SetConsoleMode(tty, ENABLE_PROCESSED_INPUT | ENABLE_MOUSE_INPUT);
+	return result;
+}
+#endif
+
+/*
+ * Get the number of lines to scroll when mouse wheel is moved.
+ */
+	public int
+default_wheel_lines(VOID_PARAM)
 {
+	int lines = 1;
 #if MSDOS_COMPILER==WIN32C
-	SetConsoleMode((HANDLE)tty, console_mode);
-	CloseHandle((HANDLE)tty);
+	if (SystemParametersInfo(SPI_GETWHEELSCROLLLINES, 0, &lines, 0))
+	{
+		if (lines == WHEEL_PAGESCROLL)
+			lines = 3;
+	}
 #endif
+	return lines;
 }
 
 /*
  * Get a character from the keyboard.
  */
 	public int
-getchr()
+getchr(VOID_PARAM)
 {
 	char c;
 	int result;
@@ -112,7 +150,7 @@ getchr()
 #if MSDOS_COMPILER==WIN32C
 		if (ABORT_SIGS())
 			return (READ_INTR);
-		c = WIN32getch(tty);
+		c = WIN32getch();
 #else
 		c = getch();
 #endif
@@ -157,7 +195,7 @@ getchr()
 			else if (c >= 'A' && c <= 'F')
 				v = c - 'A' + 10;
 			else
-				hex_in = 0;
+				v = 0;
 			hex_value = (hex_value << 4) | v;
 			if (--hex_in > 0)
 			{
diff --git a/ubin.uni b/ubin.uni
index 888fe75ca841..a8d4b544aec0 100644
--- a/ubin.uni
+++ b/ubin.uni
@@ -1,4 +1,4 @@
-/* Generated by "./mkutable -f2 Cc Cs Co Zl Zp -- unicode/UnicodeData.txt" on Tue Jul 25 09:04:35 PDT 2017 */
+/* Generated by "./mkutable -f2 Cc Cs Co Zl Zp -- unicode/UnicodeData.txt" on Wed Feb 13 17:57:06 PST 2019 */
 	{ 0x0000, 0x0007 }, /* Cc */
 	{ 0x000b, 0x000b }, /* Cc */
 	{ 0x000e, 0x001f }, /* Cc */
diff --git a/version.c b/version.c
index 1432b374e5ef..7aca8d6d5b6e 100644
--- a/version.c
+++ b/version.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1984-2017  Mark Nudelman
+ * Copyright (C) 1984-2019  Mark Nudelman
  *
  * You may distribute under the terms of either the GNU General Public
  * License or the Less License, as specified in the README file.
@@ -853,6 +853,33 @@ v527  10/30/17  Fix search hilite bug on last page with -a.
 v528  11/3/17   Make second ESC-u clear status column.
 v529  11/12/17  Display Unicode formatting chars in hex if -U is set.
 v530  12/2/17   Minor doc change and add missing VOID_PARAM.
+-----------------------------------------------------------------
+v531  5/13/18   Fix bug with v on empty file; fix bug with v on file with 
+                metachars in name; add --nohistdups option.
+v532  7/27/18   Redraw screen on SIGWINCH even if screen size doesn't change.
+v533  8/1/18    Shell escape filenames in history; use PCRE_UTF8 flag; 
+                use wide-chars for Windows console title (thanks to Jason Hood).
+v534  8/9/18    Support PCRE2.
+v535  8/16/18   Don't count lines of initial screen if using -X with -F
+                (thanks to Linus Torvalds).
+v536  8/31/18   Use descriptive error messages for PCRE2.
+v537  8/31/18   Support mingw build system (thanks to Mike Soyka).
+v538  9/3/18    Clean up some WIN32 code.
+v539  9/13/18   Fix spurious input on Windows with CAPSLOCK.
+v540  10/29/18  Add --mouse option.
+v541  10/30/18  Add --MOUSE option.
+v542  11/6/18   Add mouse support for WIN32; add --wheel-lines option.
+                (thanks to Jason Hood).
+v543  11/12/18  Code cleanup.
+v544  11/16/18  Don't init/deinit keyboard/mouse if quit due to -F.
+v545  11/22/18  Fix Windows build, memory leaks.
+v546  11/29/18  Add --save-marks option.
+v547  11/30/18  Fix some bugs with saved marks.
+v548  12/14/18  Ignore mouse input when line editing.
+v549  2/10/19   Support X11 mouse extension 1006;
+                Win32 fixes (thanks to Jason Hood).
+v550  2/16/19   Fix Win32 build; don't enable mouse unless --mouse is set.
+v551  6/10/19   Doc changes.
 */
 
-char version[] = "530";
+char version[] = "551";
diff --git a/wide.uni b/wide.uni
index 801a3525e4a5..e23ba7344927 100644
--- a/wide.uni
+++ b/wide.uni
@@ -1,4 +1,4 @@
-/* Generated by "./mkutable -f1 W F -- unicode/EastAsianWidth.txt" on Tue Jul 25 09:04:35 PDT 2017 */
+/* Generated by "./mkutable -f1 W F -- unicode/EastAsianWidth.txt" on Thu Feb 14 08:30:47 PST 2019 */
 	{ 0x1100, 0x115f }, /* W */
 	{ 0x231a, 0x231b }, /* W */
 	{ 0x2329, 0x232a }, /* W */
@@ -42,7 +42,7 @@
 	{ 0x3001, 0x303e }, /* W */
 	{ 0x3041, 0x3096 }, /* W */
 	{ 0x3099, 0x30ff }, /* W */
-	{ 0x3105, 0x312e }, /* W */
+	{ 0x3105, 0x312f }, /* W */
 	{ 0x3131, 0x318e }, /* W */
 	{ 0x3190, 0x31ba }, /* W */
 	{ 0x31c0, 0x31e3 }, /* W */
@@ -62,7 +62,7 @@
 	{ 0xff01, 0xff60 }, /* F */
 	{ 0xffe0, 0xffe6 }, /* F */
 	{ 0x16fe0, 0x16fe1 }, /* W */
-	{ 0x17000, 0x187ec }, /* W */
+	{ 0x17000, 0x187f1 }, /* W */
 	{ 0x18800, 0x18af2 }, /* W */
 	{ 0x1b000, 0x1b11e }, /* W */
 	{ 0x1b170, 0x1b2fb }, /* W */
@@ -97,12 +97,14 @@
 	{ 0x1f6cc, 0x1f6cc }, /* W */
 	{ 0x1f6d0, 0x1f6d2 }, /* W */
 	{ 0x1f6eb, 0x1f6ec }, /* W */
-	{ 0x1f6f4, 0x1f6f8 }, /* W */
+	{ 0x1f6f4, 0x1f6f9 }, /* W */
 	{ 0x1f910, 0x1f93e }, /* W */
-	{ 0x1f940, 0x1f94c }, /* W */
-	{ 0x1f950, 0x1f96b }, /* W */
-	{ 0x1f980, 0x1f997 }, /* W */
-	{ 0x1f9c0, 0x1f9c0 }, /* W */
-	{ 0x1f9d0, 0x1f9e6 }, /* W */
+	{ 0x1f940, 0x1f970 }, /* W */
+	{ 0x1f973, 0x1f976 }, /* W */
+	{ 0x1f97a, 0x1f97a }, /* W */
+	{ 0x1f97c, 0x1f9a2 }, /* W */
+	{ 0x1f9b0, 0x1f9b9 }, /* W */
+	{ 0x1f9c0, 0x1f9c2 }, /* W */
+	{ 0x1f9d0, 0x1f9ff }, /* W */
 	{ 0x20000, 0x2fffd }, /* W */
 	{ 0x30000, 0x3fffd }, /* W */