NAME

       getsid - get session ID

LIBRARY

       Standard C library (libc, -lc)

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()  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 is returned, and errno is set to indicate the
       error.

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

       Linux does not return EPERM.

STANDARDS

       POSIX.1-2008.

HISTORY

       POSIX.1-2001, SVr4.  Linux 2.0.

NOTES

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

SEE ALSO

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