--- Makefile.orig	2003-03-10 10:33:41.000000000 +0800
+++ Makefile	2014-06-29 23:19:14.368465195 +0800
@@ -4,10 +4,9 @@
 prefix		= /usr/local
 exec_prefix	= /usr/local
 bindir		= $(prefix)/bin
-mandir		= $(prefix)/man
-man1dir		= $(mandir)/man1
+mandir		= $(prefix)/man/man1
 
-CC		= gcc
+CC		?= gcc
 CFLAGS		= -g -O
 LDFLAGS		=
 LIBS		=
@@ -25,10 +24,8 @@ tai64nfrac.1: tai64nfrac.pod
 	    --section=1 $< > $@
 
 install: tai64nfrac tai64nfrac.1
-	mkdir -p $(bindir)
-	cp tai64nfrac $(bindir)
-	mkdir -p $(man1dir)
-	cp tai64nfrac.1 $(man1dir)
+	$(BSD_INSTALL_PROGRAM) tai64nfrac $(DESTDIR)$(bindir)
+	$(BSD_INSTALL_MAN) tai64nfrac.1 $(DESTDIR)$(mandir)
 
 clean:
 	rm -f *.o tai64nfrac