setsid(2) [osx man page]

SETSID(2)						      BSD System Calls Manual							 SETSID(2)

NAME

     setsid -- create session and set process group ID

SYNOPSIS

     #include <unistd.h>

     pid_t
     setsid(void);

DESCRIPTION

     The setsid function creates a new session.  The calling process is the session leader of the new session, is the process group leader of a
     new process group and has no controlling terminal.  The calling process is the only process in either the session or the process group.

     Upon successful completion, the setsid function returns the value of the process group ID of the new process group, which is the same as the
     process ID of the calling process.

ERRORS

     If an error occurs, setsid returns -1 and the global variable errno is set to indicate the error, as follows:

     [EPERM]		The calling process is already a process group leader, or the process group ID of a process other than the calling process
			matches the process ID of the calling process.

LEGACY SYNOPSIS

     #include <sys/types.h>
     #include <unistd.h>

     The include file <sys/types.h> is necessary.

SEE ALSO

     setpgid(3), tcgetpgrp(3), tcsetpgrp(3), compat(5)

STANDARDS

     The setsid function is expected to be compliant with the IEEE Std 1003.1-1988 (``POSIX.1'') specification.

BSD
								   June 4, 1993 							       BSD

Check Out this Related Man Page

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 controlling tty.  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 session.

RETURN VALUE

       The session ID of the calling process.

ERRORS

       On  error,  -1  will be returned.  The only error which can happen is EPERM. It is returned when the process group ID of any process equals
       the PID of the calling process. Thus, in particular, setsid fails if the calling process is already a process group leader.

NOTES

       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	and  exit,
       and have the child do setsid().

CONFORMING TO

       POSIX, SVr4.

SEE ALSO

       setpgid(2), setpgrp(2)

Linux 1.0.0							    1994-08-27								 SETSID(2)

Linux and UNIX Man Pages

setsid(2) [osx man page]

Check Out this Related Man Page