GETSID(2)		   Linux Programmer's Manual		     GETSID(2)



NAME
       getsid - get session ID

SYNOPSIS
       #include <unistd.h>

       pid_t getsid(pid_t pid);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       getsid():
	   _XOPEN_SOURCE >= 500
	       || /* Since glibc 2.12: */ _POSIX_C_SOURCE >= 200809L

DESCRIPTION
       getsid(0)  returns  the	session	 ID  of the calling process.  getsid()
       returns the session ID of the process with process ID pid.  If  pid  is
       0, getsid() returns the session ID of the calling process.

RETURN VALUE
       On  success,  a	session	 ID is returned.  On error, (pid_t) -1 will be
       returned, and errno is set appropriately.

ERRORS
       EPERM  A process with process ID pid exists, but it is not in the  same
	      session as the calling process, and the implementation considers
	      this an error.

       ESRCH  No process with process ID pid was found.

VERSIONS
       This system call is available on Linux since version 2.0.

CONFORMING TO
       POSIX.1-2001, POSIX.1-2008, SVr4.

NOTES
       Linux does not return EPERM.

       See credentials(7) for a description of sessions and session IDs.

SEE ALSO
       getpgid(2), setsid(2), credentials(7)

COLOPHON
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       description  of	the project, information about reporting bugs, and the
       latest	 version    of	  this	  page,	   can	   be	  found	    at
       https://www.kernel.org/doc/man-pages/.



Linux				  2016-10-08			     GETSID(2)