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

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

NOTES

       Linux does not return EPERM.

SEE ALSO

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

COLOPHON

       This  page  is  part of release 4.04 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 http://www.kernel.org/doc/man-pages/.