fuse.4: ffix

[thirdparty/man-pages.git] / man2 / setsid.2

diff --git a/man2/setsid.2 b/man2/setsid.2
index ac494d98a92dc4cddda703a6d6c496a3531c1f95..d2f4cc3b2b1331385b1062647fa9d2421dfcdfab 100644 (file)
--- a/man2/setsid.2
+++ b/man2/setsid.2
@@ -28,13 +28,15 @@
 .\"    tiny changes from a man page by Charles Livingston).
 .\" Modified Sun Jul 21 14:45:46 1996 <aeb@cwi.nl>
 .\"
-.TH SETSID 2 2014-12-31 "Linux" "Linux Programmer's Manual"
+.TH SETSID 2 2017-09-15 "Linux" "Linux Programmer's Manual"
 .SH NAME
 setsid \- creates a session and sets the process group ID
 .SH SYNOPSIS
 .ad l
+.B #include <sys/types.h>
+.br
 .B #include <unistd.h>
-.sp
+.PP
 .B pid_t setsid(void);
 .br
 .ad b
@@ -46,11 +48,14 @@ The calling process is the leader of the new session
 (i.e., its session ID is made the same as its process ID).
 The calling process also becomes
 the process group leader of a new process group in the session
-(i.e., its process group ID is made the same as it process ID).
-
+(i.e., its process group ID is made the same as its process ID).
+.PP
 The calling process will be the only process in
 the new process group and in the new session.
-The new session has no controlling terminal.
+.PP
+Initially, the new session has no controlling terminal.
+For details of how a session acquires a controlling terminal, see
+.BR credentials (7).
 .SH RETURN VALUE
 On success, the (new) session ID of the calling process is returned.
 On error,
@@ -66,14 +71,14 @@ Thus, in particular,
 .BR setsid ()
 fails if the calling process is already a process group leader.
 .SH CONFORMING TO
-SVr4, POSIX.1-2001.
+POSIX.1-2001, POSIX.1-2008, SVr4.
 .SH NOTES
 A child created via
 .BR fork (2)
 inherits its parent's session ID.
 The session ID is preserved across an
 .BR execve (2).
-
+.PP
 A process group leader is a process whose process group ID equals its PID.
 Disallowing a process group leader from calling
 .BR setsid ()
@@ -84,16 +89,29 @@ such a scenario would break the strict
 two-level hierarchy of sessions and process groups.
 In order to be sure that
 .BR setsid ()
-will succeed,
+will succeed, call
 .BR fork (2)
-and
+and have the parent
 .BR _exit (2),
-and have the child do
+while the child (which by definition can't be a process group leader) calls
 .BR setsid ().
+.PP
+If a session has a controlling terminal, and the
+.B CLOCAL
+flag for that terminal is not set,
+and a terminal hangup occurs, then the session leader is sent a
+.BR SIGHUP
+signal.
+.PP
+If a process that is a session leader terminates, then a
+.B SIGHUP
+signal is sent to each process in the foreground
+process group of the controlling terminal.
 .SH SEE ALSO
 .BR setsid (1),
 .BR getsid (2),
 .BR setpgid (2),
 .BR setpgrp (2),
 .BR tcgetsid (3),
-.BR credentials (7)
+.BR credentials (7),
+.BR sched (7)