# setsid(2)

## NAME

         setsid, getpgrp - create process group, get process group id

## SYNOPSIS

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

         pid_t setsid(void)
         pid_t getpgrp(void)

## DESCRIPTION

         Setsid() creates a new session if the calling process is  not  already  a
         session  leader.  The calling process becomes the session leader of a new
         process group and the process group ID of this new process group will  be
         equal  to the process ID of the new session leader.  The process group ID
         is inherited on a fork().

         Getpgrp() returns the process group ID of the calling process.

## SEE ALSO

         kill(2), termios(3), tty(4).

## DIAGNOSTICS

         Setsid() returns the new process group ID on success, or  -1  with  errno
         set to EPERM if the process is already a session leader.

## AUTHOR

         Kees J. Bot (kjb@cs.vu.nl)