+++ /dev/null
-.\" Copyright 1993 Rickard E. Faith (faith@cs.unc.edu)
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.TH GETPID 2 2014-09-21 "Linux" "Linux Programmer's Manual"
-.SH NAME
-getpid, getppid \- get process identification
-.SH SYNOPSIS
-.B #include <sys/types.h>
-.br
-.B #include <unistd.h>
-.sp
-.B pid_t getpid(void);
-.br
-.B pid_t getppid(void);
-.SH DESCRIPTION
-.BR getpid ()
-returns the process ID of the calling process.
-(This is often used by
-routines that generate unique temporary filenames.)
-
-.BR getppid ()
-returns the process ID of the parent of the calling process.
-.SH ERRORS
-These functions are always successful.
-.SH CONFORMING TO
-POSIX.1-2001, 4.3BSD, SVr4.
-.SH NOTES
-Since glibc version 2.3.4,
-the glibc wrapper function for
-.BR getpid ()
-caches PIDs,
-so as to avoid additional system calls when a process calls
-.BR getpid ()
-repeatedly.
-Normally this caching is invisible,
-but its correct operation relies on support in the wrapper functions for
-.BR fork (2),
-.BR vfork (2),
-and
-.BR clone (2):
-if an application bypasses the glibc wrappers for these system calls by using
-.BR syscall (2),
-then a call to
-.BR getpid ()
-in the child will return the wrong value
-(to be precise: it will return the PID of the parent process).
-.\" The following program demonstrates this "feature":
-.\"
-.\" #define _GNU_SOURCE
-.\" #include <sys/syscall.h>
-.\" #include <sys/wait.h>
-.\" #include <stdio.h>
-.\" #include <stdlib.h>
-.\" #include <unistd.h>
-.\"
-.\" int
-.\" main(int argc, char *argv[])
-.\" {
-.\" /* The following statement fills the getpid() cache */
-.\"
-.\" printf("parent PID = %ld\n", (long) getpid());
-.\"
-.\" if (syscall(SYS_fork) == 0) {
-.\" if (getpid() != syscall(SYS_getpid))
-.\" printf("child getpid() mismatch: getpid()=%ld; "
-.\" "syscall(SYS_getpid)=%ld\n",
-.\" (long) getpid(), (long) syscall(SYS_getpid));
-.\" exit(EXIT_SUCCESS);
-.\" }
-.\" wait(NULL);
-.\"}
-See also
-.BR clone (2)
-for discussion of a case where
-.BR getpid ()
-may return the wrong value even when invoking
-.BR clone (2)
-via the glibc wrapper function.
-.SH SEE ALSO
-.BR clone (2),
-.BR fork (2),
-.BR kill (2),
-.BR exec (3),
-.BR mkstemp (3),
-.BR tempnam (3),
-.BR tmpfile (3),
-.BR tmpnam (3),
-.BR credentials (7),
-.BR pid_namespaces (7)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I 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/.
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