Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
SETSID(2)		   Linux Programmer's Manual		     SETSID(2)

NAME
       setsid -	creates	a session and sets the process group ID

SYNOPSIS
       #include	<unistd.h>

       pid_t setsid(void);

DESCRIPTION
       setsid()	 creates a new session if the calling process is not a process
       group leader.  The calling process is the leader	of  the	 new  session,
       the  process group leader of the	new process group, and has no control-
       ling terminal.  The process group ID and	 session  ID  of  the  calling
       process are set to the PID of the calling process.  The calling process
       will be the only	process	in this	new process group and in this new ses-
       sion.

RETURN VALUE
       On  success,  the  (new)	session	ID of the calling process is returned.
       On error, (pid_t) -1 is returned, and errno is set to indicate the  er-
       ror.

ERRORS
       EPERM  The  process group ID of any process equals the PID of the call-
	      ing process.  Thus, in particular, setsid() fails	if the calling
	      process is already a process group leader.

CONFORMING TO
       SVr4, POSIX.1-2001.

NOTES
       A child created via fork(2) inherits its	parent's session ID.  The ses-
       sion ID is preserved across an execve(2).

       A process group leader is a process with	process	group ID equal to  its
       PID.   In  order	 to  be	 sure  that setsid() will succeed, fork(2) and
       _exit(2), and have the child do setsid().

SEE ALSO
       setsid(1),  getsid(2),  setpgid(2),  setpgrp(2),	 tcgetsid(3),  creden-
       tials(7)

COLOPHON
       This  page  is  part of release 3.74 of the Linux man-pages project.  A
       description of the project, information about reporting bugs,  and  the
       latest	  version     of     this    page,    can    be	   found    at
       http://www.kernel.org/doc/man-pages/.

Linux				  2013-02-11			     SETSID(2)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | CONFORMING TO | NOTES | SEE ALSO | COLOPHON

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=setsid&sektion=2&manpath=Debian+8.1.0>

home | help