getsid(2) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | VERSIONS | CONFORMING TO | NOTES | SEE ALSO | COLOPHON

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

NAME top

       getsid - get session ID

SYNOPSIS top

       #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 top

       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 top

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

ERRORS top

       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 top

       This system call is available on Linux since version 2.0.

CONFORMING TO top

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

NOTES top

       Linux does not return EPERM.

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

SEE ALSO top

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

COLOPHON top

       This page is part of release 5.08 of the Linux man-pages project.  A
       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                            2017-09-15                        GETSID(2)

Pages that refer to this page: procps(1) , ps(1) , setsid(2) , syscalls(2) , sd_peer_get_cgroup(3) , sd_peer_get_machine_name(3) , sd_peer_get_owner_uid(3) , sd_peer_get_session(3) , sd_peer_get_slice(3) , sd_peer_get_unit(3) , sd_peer_get_user_slice(3) , sd_peer_get_user_unit(3) , sd_pid_get_cgroup(3) , sd_pid_get_machine_name(3) , sd_pid_get_owner_uid(3) , sd_pid_get_session(3) , sd_pid_get_slice(3) , sd_pid_get_unit(3) , sd_pid_get_user_slice(3) , sd_pid_get_user_unit(3) , tcgetsid(3) , utmp(5) , utmpx(5) , wtmp(5) , credentials(7)