V8/usr/man/man3/memory.3

.TH MEMORY 3
.SH NAME
memccpy, memchr, memcmp, memcpy, memset \- memory operations
.SH SYNOPSIS
.nf
.B char *memccpy (s1, s2, c, n)
.B char *s1, *s2;
.B int c, n;
.PP
.B char *memchr (s, c, n)
.B char *s;
.B int c, n;
.PP
.B int memcmp (s1, s2, n)
.B char *s1, *s2;
.B int n;
.PP
.B char *memcpy (s1, s2, n)
.B char *s1, *s2;
.B int n;
.PP
.B char *memset (s, c, n)
.B char *s;
.B int c, n;
.fi
.SH DESCRIPTION
These functions operate as efficiently as possible on memory areas
(arrays of characters bounded by a count, not terminated by a null character).
They do not check for the overflow of any receiving memory area.
.PP
.I Memccpy
copies characters from memory area
.I s2
into
.IR s1 ,
stopping after the first occurrence of character
.I c
has been copied, or after
.I n
characters have been copied, whichever comes first.
It returns a pointer to the character after
the copy of
.I c
in
.IR s1 ,
or zero if
.I c
was not found in the first
.I n
characters of
.IR s2 .
.PP
.PP
.I Memchr
returns a pointer to the first
occurrence of character 
.I c
in the first
.I n
characters of memory area
.IR s,
or zero if
.I c
does not occur.
.PP
.I Memcmp
compares its arguments, looking at the first
.I n
characters only, and returns an integer
less than, equal to, or greater than 0,
according as
.I s1
is lexicographically less than, equal to, or
greater than
.IR s2 .
.PP
.I Memcpy
copies
.I n
characters from memory area
.I s2
to
.IR s1 .
It returns
.IR s1 .
.PP
.I Memset
sets the first
.I n
characters in memory area
.I s
to the value of character
.IR c .
It returns
.IR s .
.SH SEE ALSO
string(3)
.SH BUGS
.I Memcmp
use native character comparison, which is signed
on some machines, unsigned on others;
thus the sign of the value returned when a
character has its high-order bit set is implementation-dependent.
.br
The outcome of overlapping moves varies among implementations.
.\"	@(#)memory.3c	6.2 of 10/20/83