getsid(3p) — Linux manual page

GETSID(3P)              POSIX Programmer's Manual             GETSID(3P)

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(1p), fork(3p), getpid(3p), getpgid(3p), setpgid(3p),
       setsid(3p)

       The Base Definitions volume of POSIX.1‐2017, unistd.h(0p)

COPYRIGHT 

       Portions of this text are reprinted and reproduced in electronic
       form from IEEE Std 1003.1-2017, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The
       Open Group Base Specifications Issue 7, 2018 Edition, Copyright
       (C) 2018 by the Institute of Electrical and Electronics
       Engineers, Inc and The Open Group.  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.opengroup.org/unix/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 .

IEEE/The Open Group               2017                        GETSID(3P)

Pages that refer to this page: unistd.h(0p), getpgid(3p), setpgrp(3p), setsid(3p)

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https://man7.org/linux/man-pages/man3/getsid.3p.html