.\"	$NetBSD: reallocarr.3,v 1.4 2015/07/28 17:13:34 kamil Exp $
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.Dd February 19, 2015
.Dt REALLOCARR 3
.Os
.Sh NAME
.Nm reallocarr
.Nd reallocate array
.Sh SYNOPSIS
.In stdlib.h
.Ft int
.Fo reallocarr
.Fa "void *ptr"
.Fa "size_t number"
.Fa "size_t size"
.Fc
.Sh DESCRIPTION
The
.Nm
function reallocates the memory in
.Fa *ptr .
.Sh RETURN VALUES
On successful completion,
.Fn
returns 0 and updates
.Fa *ptr .
Otherwise, an error code (see
.Xr errno 2 )
is returned and
.Fa *ptr
and the referenced memory is unmodified.
.Sh EXAMPLES
The following uses
.Fn reallocarr
to initialize an array of INITSIZE integers, then
resizes it to NEWSIZE elements:
.Bd -literal -offset indent
int *data = NULL;
int ret = 0;

ret = reallocarr(&data, INITSIZE, sizeof(*data));
if (ret)
    errc(1, ret, "reallocarr failed");

ret = reallocarr(&data, NEWSIZE, sizeof(*data));
if (ret)
    errc(1, ret, "reallocarr failed on resize");
.Ed
.Sh SEE ALSO
.Xr calloc 3
.Sh HISTORY
.Nm
first appeared in
.Nx 7.0 .
.Ox
introduced the
.Xr reallocarray 3
function for the same purpose, but the interface makes it difficult
to correctly handle zero-sized allocations.