PR_SET_CHILD_SUBREAPER(2const) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | STANDARDS | HISTORY | SEE ALSO | COLOPHON

PR_SET_CHILD_SUBREAPER(2const)            PR_SET_CHILD_SUBREAPER(2const)

NAME         top

       PR_SET_CHILD_SUBREAPER - set/unset the "child subreaper"
       attribute of the calling process

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <linux/prctl.h>  /* Definition of PR_* constants */
       #include <sys/prctl.h>

       int prctl(PR_SET_CHILD_SUBREAPER, long set);

DESCRIPTION         top

       If set is nonzero, set the "child subreaper" attribute of the
       calling process; if set is zero, unset the attribute.

       A subreaper fulfills the role of init(1) for its descendant
       processes.  When a process becomes orphaned (i.e., its immediate
       parent terminates), then that process will be reparented to the
       nearest still living ancestor subreaper.  Subsequently, calls to
       getppid(2) in the orphaned process will now return the PID of the
       subreaper process, and when the orphan terminates, it is the
       subreaper process that will receive a SIGCHLD signal and will be
       able to wait(2) on the process to discover its termination
       status.

       The setting of the "child subreaper" attribute is not inherited
       by children created by fork(2) and clone(2).  The setting is
       preserved across execve(2).

       Establishing a subreaper process is useful in session management
       frameworks where a hierarchical group of processes is managed by
       a subreaper process that needs to be informed when one of the
       processes—for example, a double-forked daemon—terminates (perhaps
       so that it can restart that process).  Some init(1) frameworks
       (e.g., systemd(1)) employ a subreaper process for similar
       reasons.

RETURN VALUE         top

       On success, 0 is returned.  On error, -1 is returned, and errno
       is set to indicate the error.

STANDARDS         top

       Linux.

HISTORY         top

       Linux 3.4.

SEE ALSO         top

       prctl(2), PR_GET_CHILD_SUBREAPER(2const)

COLOPHON         top

       This page is part of the man-pages (Linux kernel and C library
       user-space interface documentation) project.  Information about
       the project can be found at 
       ⟨https://www.kernel.org/doc/man-pages/⟩.  If you have a bug report
       for this manual page, see
       ⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩.
       This page was obtained from the tarball man-pages-6.9.1.tar.gz
       fetched from
       ⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on
       2024-06-26.  If you discover any rendering problems in this HTML
       version of the page, or you believe there is a better or more up-
       to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not
       part of the original manual page), send a mail to
       man-pages@man7.org

Linux man-pages 6.9.1          2024-06-02 PR_SET_CHILD_SUBREAPER(2const)

Pages that refer to this page: prctl(2)PR_GET_CHILD_SUBREAPER(2const)PR_SET_PDEATHSIG(2const)