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 || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
|| /* Since glibc 2.12: */ _POSIX_C_SOURCE >= 200809L
DESCRIPTION
getsid(0) returns the session ID of the calling process. getsid(p)
returns the session ID of the process with process ID p. (The session
ID of a process is the process group ID of the session leader.)
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 p 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 p was found.
VERSIONS
This system call is available on Linux since version 2.0.
CONFORMING TO
SVr4, POSIX.1-2001.
NOTES
Linux does not return EPERM.
SEE ALSO
getpgid(2), setsid(2), credentials(7)
COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2010-09-26 GETSID(2)