.\"	$OpenBSD: memcpy.3,v 1.8 2011/07/25 00:38:52 schwarze Exp $
.\"
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.\" This code is derived from software contributed to Berkeley by
.\" Chris Torek and the American National Standards Committee X3,
.\" on Information Processing Systems.
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.Dd $Mdocdate: July 25 2011 $
.Dt MEMCPY 3
.Os
.Sh NAME
.Nm memcpy
.Nd copy bytes
.Sh SYNOPSIS
.Fd #include <string.h>
.Ft void *
.Fn memcpy "void *dst" "const void *src" "size_t len"
.Sh DESCRIPTION
The
.Fn memcpy
function copies
.Fa len
bytes from buffer
.Fa src
to buffer
.Fa dst .
.Sh RETURN VALUES
The
.Fn memcpy
function returns the original value of
.Fa dst .
.Sh SEE ALSO
.Xr bcopy 3 ,
.Xr memccpy 3 ,
.Xr memmove 3 ,
.Xr strcpy 3 ,
.Xr strlcpy 3 ,
.Xr wmemcpy 3
.Sh STANDARDS
The
.Fn memcpy
function conforms to
.St -ansiC .
.Sh HISTORY
The
.Fn memcpy
function first appeared in
.At V
and was reimplemented for
.Bx 4.3 Tahoe .
.Sh CAVEATS
In this implementation
.Fn memcpy
is implemented using
.Xr bcopy 3 ,
and therefore the buffers may overlap.
On other systems, copying overlapping buffers may produce surprises.
A portable, safe solution is to use
.Xr memmove 3 .