1.\" Copyright (c) 1980, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)getpid.2 8.1 (Berkeley) 6/4/93 29.\" $FreeBSD$ 30.\" 31.Dd December 15, 2015 32.Dt GETPID 2 33.Os 34.Sh NAME 35.Nm getpid , 36.Nm getppid 37.Nd get parent or calling process identification 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In unistd.h 42.Ft pid_t 43.Fn getpid void 44.Ft pid_t 45.Fn getppid void 46.Sh DESCRIPTION 47The 48.Fn getpid 49system call 50returns 51the process ID of 52the calling process. 53Though the ID is guaranteed to be unique, it should 54.Em NOT 55be used for constructing temporary file names, for 56security reasons; see 57.Xr mkstemp 3 58instead. 59.Pp 60The 61.Fn getppid 62system call 63returns the process ID of the parent 64of the calling process. 65.Sh ERRORS 66The 67.Fn getpid 68and 69.Fn getppid 70system calls are always successful, and no return value is reserved to 71indicate an error. 72.Sh SEE ALSO 73.Xr fork 2 , 74.Xr getpgrp 2 , 75.Xr kill 2 , 76.Xr setpgid 2 , 77.Xr setsid 2 , 78.Xr exec 3 79.Sh STANDARDS 80The 81.Fn getpid 82and 83.Fn getppid 84system calls are expected to conform to 85.St -p1003.1-90 . 86.Sh HISTORY 87The 88.Fn getpid 89function appeared in 90.At v7 . 91