xref: /freebsd/lib/libsys/getpid.2 (revision 8269e7673cf033aba67dab8264fe719920c70f87)

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.Dd December 15, 2015
.Dt GETPID 2
.Os
.Sh NAME
.Nm getpid ,
.Nm getppid
.Nd get parent or calling process identification
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In unistd.h
.Ft pid_t
.Fn getpid void
.Ft pid_t
.Fn getppid void
.Sh DESCRIPTION
The
.Fn getpid
system call
returns
the process ID of
the calling process.
Though the ID is guaranteed to be unique, it should
.Em NOT
be used for constructing temporary file names, for
security reasons; see
.Xr mkstemp 3
instead.
.Pp
The
.Fn getppid
system call
returns the process ID of the parent
of the calling process.
.Sh ERRORS
The
.Fn getpid
and
.Fn getppid
system calls are always successful, and no return value is reserved to
indicate an error.
.Sh SEE ALSO
.Xr fork 2 ,
.Xr getpgrp 2 ,
.Xr kill 2 ,
.Xr setpgid 2 ,
.Xr setsid 2 ,
.Xr exec 3
.Sh STANDARDS
The
.Fn getpid
and
.Fn getppid
system calls are expected to conform to
.St -p1003.1-90 .
.Sh HISTORY
The
.Fn getpid
function appeared in
.At v7 .