.\" Copyright (c) 1990, 1991, 1993
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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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.\"     @(#)memcpy.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: head/lib/libc/string/memcpy.3 251069 2013-05-28 20:57:40Z emaste $
.\"
.Dd June 4, 1993
.Dt MEMCPY 3
.Os
.Sh NAME
.Nm memcpy
.Nd copy byte string
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In 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 string
.Fa src
to string
.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 wmemcpy 3
.Sh STANDARDS
The
.Fn memcpy
function
conforms to
.St -isoC .
.Sh BUGS
In this implementation
.Fn memcpy
is implemented using
.Xr bcopy 3 ,
and therefore the strings may overlap.
On other systems, copying overlapping strings may produce surprises.
Programs intended to be portable should use
.Xr memmove 3
when
.Fa src
and
.Fa dst
may overlap.