alloca.3   [plain text]


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.\"     @(#)alloca.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/stdlib/alloca.3,v 1.11 2003/06/28 22:12:30 ru Exp $
.\"
.Dd June 4, 1993
.Dt ALLOCA 3
.Os
.Sh NAME
.Nm alloca
.Nd memory allocator
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In alloca.h
or
.br
.In stdlib.h
.Ft void *
.Fn alloca "size_t size"
.Sh DESCRIPTION
The
.Fn alloca
function
allocates
.Fa size
bytes of space in the stack frame of the caller.
This temporary space is automatically freed on
return.
.Sh RETURN VALUES
The
.Fn alloca
function returns a pointer to the beginning of the allocated space.
If the allocation failed, a
.Dv NULL
pointer is returned.
.Sh SEE ALSO
.Xr brk 2 ,
.Xr calloc 3 ,
.Xr getpagesize 3 ,
.Xr malloc 3 ,
.Xr realloc 3
.Sh HISTORY
The
.Fn alloca
function appeared in
.At 32v .
.\" .Bx ?? .
.\" The function appeared in 32v, pwb and pwb.2 and in 3bsd 4bsd
.\" The first man page (or link to a man page that I can find at the
.\" moment is 4.3...
.Sh BUGS
The
.Fn alloca
function
is machine and compiler dependent;
its use is discouraged.