memory(3C)memory(3C)NAME
memory: memccpy, memchr, memcmp, memcpy, memmove, memset - memory
operations
SYNOPSIS
#include <string.h>
void *memccpy (void *s1, const void *s2, int c, size_t n);
void *memchr (const void *s, int c, size_t n);
int memcmp (const void *s1, const void *s2, size_t n);
void *memcpy (void *s1, const void *s2, size_t n);
void *memmove (void *s1, const void *s2, size_t n);
void *memset (void *s, int c, size_t n);
DESCRIPTION
These functions operate as efficiently as possible on memory areas
(arrays of bytes bounded by a count, not terminated by a null character).
They do not check for the overflow of any receiving memory area.
memccpy copies bytes from memory area s2 into s1, stopping after the
first occurrence of c (converted to an unsigned char) has been copied, or
after n bytes have been copied, whichever comes first. It returns a
pointer to the byte after the copy of c in s1, or a null pointer if c was
not found in the first n bytes of s2.
memchr returns a pointer to the first occurrence of c (converted to an
unsigned char) in the first n bytes (each interpreted as an unsigned
char) of memory area s, or a null pointer if c does not occur.
memcmp compares its arguments, looking at the first n bytes (each
interpreted as an unsigned char), and returns an integer less than, equal
to, or greater than 0, according as s1 is lexicographically less than,
equal to, or greater than s2 when taken to be unsigned characters.
memcpy copies n bytes from memory area s2 to s1. It returns s1.
memmove copies n bytes from memory areas s2 to s1. Copying between
objects that overlap will take place correctly. It returns s1.
memset sets the first n bytes in memory area s to the value of c
(converted to an unsigned char). It returns s.
SEE ALSOstring(3C).
Page 1
memory(3C)memory(3C)CAVEATS
For maximum portability, memmove should be used when the memory areas
indicated by s1 and s2 may overlap, and memcpy used for faster copying
between non-overlapping areas. In this implementation, however, memcpy
is an efficient copying algorithm which correctly handles overlapping
areas.
Page 2
