GETSID(2) Linux Programmer's Manual GETSID(2)
NAME
getsid - get session ID
SYNOPSIS
#include <sys/types.h>
#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() re-
turns 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 re-
turned, 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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latest version of this page, can be found at
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Linux 2017-09-15 GETSID(2)