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Diffstat (limited to 'gnu/uucp/libunix/detach.c')
| -rw-r--r-- | gnu/uucp/libunix/detach.c | 186 |
1 files changed, 0 insertions, 186 deletions
diff --git a/gnu/uucp/libunix/detach.c b/gnu/uucp/libunix/detach.c deleted file mode 100644 index 41e1969b5efc..000000000000 --- a/gnu/uucp/libunix/detach.c +++ /dev/null @@ -1,186 +0,0 @@ -/* detach.c - Detach from the controlling terminal. - - Copyright (C) 1992 Ian Lance Taylor - - This file is part of the Taylor UUCP package. - - This program is free software; you can redistribute it and/or - modify it under the terms of the GNU General Public License as - published by the Free Software Foundation; either version 2 of the - License, or (at your option) any later version. - - This program is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - - The author of the program may be contacted at ian@airs.com or - c/o Infinity Development Systems, P.O. Box 520, Waltham, MA 02254. - */ - -#include "uucp.h" - -#include "uudefs.h" -#include "system.h" -#include "sysdep.h" - -#include <errno.h> - -#if HAVE_SYS_IOCTL_H -#include <sys/ioctl.h> -#endif - -#ifdef TIOCNOTTY -#define HAVE_TIOCNOTTY 1 -#else -#define HAVE_TIOCNOTTY 0 -#endif - -#if HAVE_FCNTL_H -#include <fcntl.h> -#else -#if HAVE_SYS_FILE_H -#include <sys/file.h> -#endif -#endif - -#ifndef O_RDONLY -#define O_RDONLY 0 -#define O_WRONLY 1 -#define O_RDWR 2 -#endif - -/* Detach from the controlling terminal. This is called by uucico if - it is calling out to another system, so that it can receive SIGHUP - signals from the port it calls out on. It is also called by uucico - just before it starts uuxqt, so that uuxqt is completely - independent of the terminal. */ - -void -usysdep_detach () -{ -#if ! HAVE_BSD_PGRP || ! HAVE_TIOCNOTTY - - pid_t igrp; - - /* First make sure we are not a process group leader. If we have - TIOCNOTTY, this doesn't matter, since TIOCNOTTY sets our process - group to 0 anyhow. */ - -#if HAVE_BSD_PGRP - igrp = getpgrp (0); -#else - igrp = getpgrp (); -#endif - - if (igrp == getpid ()) - { - boolean fignored; - pid_t ipid; - - /* Ignore SIGHUP, since our process group leader is about to - die. */ - usset_signal (SIGHUP, SIG_IGN, FALSE, &fignored); - - ipid = ixsfork (); - if (ipid < 0) - ulog (LOG_FATAL, "fork: %s", strerror (errno)); - - if (ipid != 0) - _exit (EXIT_SUCCESS); - - /* We'll always wind up as a child of process number 1, right? - Right? We have to wait for our parent to die before - reenabling SIGHUP. */ - while (getppid () != 1) - sleep (1); - - ulog_id (getpid ()); - - /* Restore SIGHUP catcher if it wasn't being ignored. */ - if (! fignored) - usset_signal (SIGHUP, ussignal, TRUE, (boolean *) NULL); - } - -#endif /* ! HAVE_BSD_PGRP || ! HAVE_TIOCNOTTY */ - -#if HAVE_TIOCNOTTY - /* Lose the original controlling terminal. If standard input has - been reopened to /dev/null, this will do no harm. If another - port has been opened to become the controlling terminal, it - should have been detached when it was closed. */ - (void) ioctl (0, TIOCNOTTY, (char *) NULL); -#endif - - /* Close stdin, stdout and stderr and reopen them on /dev/null, to - make sure we have no connection at all to the terminal. */ - (void) close (0); - (void) close (1); - (void) close (2); - if (open ((char *) "/dev/null", O_RDONLY) != 0 - || open ((char *) "/dev/null", O_WRONLY) != 1 - || open ((char *) "/dev/null", O_WRONLY) != 2) - ulog (LOG_FATAL, "open (/dev/null): %s", strerror (errno)); - -#if HAVE_BSD_PGRP - - /* Make sure our process group ID is set to 0. On BSD TIOCNOTTY - should already have set it 0, so this will do no harm. On System - V we presumably did not execute the TIOCNOTTY call, but the - System V setpgrp will detach the controlling terminal anyhow. - This lets us use the same code on both BSD and System V, provided - it compiles correctly, which life easier for the configure - script. We don't output an error if we got EPERM because some - BSD variants don't permit this usage of setpgrp (which means they - don't provide any way to pick up a new controlling terminal). */ - - if (setpgrp (0, 0) < 0) - { - if (errno != EPERM) - ulog (LOG_ERROR, "setpgrp: %s", strerror (errno)); - } - -#else /* ! HAVE_BSD_PGRP */ - -#if HAVE_SETSID - - /* Under POSIX the setsid call creates a new session for which we - are the process group leader. It also detaches us from our - controlling terminal. I'm using the BSD setpgrp call first - because they should be equivalent for my purposes, but it turns - out that on Ultrix 4.0 setsid prevents us from ever acquiring - another controlling terminal (it does not change our process - group, and Ultrix 4.0 prevents us from setting our process group - to 0). */ - (void) setsid (); - -#else /* ! HAVE_SETSID */ - -#if HAVE_SETPGRP - - /* Now we assume we have the System V setpgrp, which takes no - arguments, and we couldn't compile the HAVE_BSD_PGRP code above - because there was a prototype somewhere in scope. On System V - setpgrp makes us the leader of a new process group and also - detaches the controlling terminal. */ - - if (setpgrp () < 0) - ulog (LOG_ERROR, "setpgrp: %s", strerror (errno)); - -#else /* ! HAVE_SETPGRP */ - - #error Must detach from controlling terminal - -#endif /* HAVE_SETPGRP */ -#endif /* ! HAVE_SETSID */ -#endif /* ! HAVE_BSD_PGRP */ - - /* At this point we have completely detached from our controlling - terminal. The next terminal device we open will probably become - our controlling terminal. */ -} |