PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of
       this interface may differ (consult the corresponding Linux  manual  page  for  details  of
       Linux behavior), or the interface may not be implemented on Linux.

NAME

       getsid — get the process group ID of a session leader

SYNOPSIS

       #include <unistd.h>

       pid_t getsid(pid_t pid);

DESCRIPTION

       The getsid() function shall obtain the process group ID of the process that is the session
       leader of the process specified by pid.  If pid is  (pid_t)0,  it  specifies  the  calling
       process.

RETURN VALUE

       Upon  successful  completion,  getsid()  shall  return the process group ID of the session
       leader of the specified process. Otherwise, it shall return −1 and set errno  to  indicate
       the error.

ERRORS

       The getsid() function shall fail if:

       EPERM  The process specified by pid is not in the same session as the calling process, and
              the implementation does not allow access to the process group  ID  of  the  session
              leader of that process from the calling process.

       ESRCH  There is no process with a process ID equal to pid.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       exec, fork(), getpid(), getpgid(), setpgid(), setsid()

       The Base Definitions volume of POSIX.1‐2008, <unistd.h>

COPYRIGHT

       Portions  of  this  text  are  reprinted  and  reproduced in electronic form from IEEE Std
       1003.1, 2013 Edition, Standard for Information Technology  --  Portable  Operating  System
       Interface  (POSIX),  The Open Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc  and  The  Open  Group.   (This  is
       POSIX.1-2008  with  the  2013  Technical  Corrigendum  1  applied.)  In  the  event of any
       discrepancy between this version and the original IEEE and The Open  Group  Standard,  the
       original  IEEE  and The Open Group Standard is the referee document. The original Standard
       can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are most  likely  to  have
       been  introduced  during  the conversion of the source files to man page format. To report
       such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .