NAME
wmemchr(), wmemcmp(), wmemcpy(), wmemmove(), wmemset() — memory operations based on wide-character
SYNOPSIS
#include <wchar.h>
wchar_t *wmemchr(const wchar_t *ws, wchar_t wc, size_t n);
int wmemcmp(const wchar_t *ws1, const wchar_t *ws2, size_t n);
wchar_t *wmemcpy(wchar_t *__restrict ws1, const wchar_t *__restrict ws2, size_t n);
wchar_t *wmemmove(wchar_t *ws1, const wchar_t *ws2, size_t n);
wchar_t *wmemset(wchar_t *ws, wchar_t wc, size_t n);
DESCRIPTION
These functions operate as efficiently as possible on memory areas (arrays of
wide-characters bounded by a count, not terminated by a null wide-character).
They do not check for the overflow of any receiving memory area.
These functions are not affected by locale and all
wchar_t
values are treated identically.
The null wide-character and
wchar_t
values not corresponding to valid characters are not treated specially.
- wmemchr()
The
wmemchr()
function locates the first occurrence of
wc
in the initial
n
wide-characters of the object pointed to by
ws.
The
wmemchr()
function returns a pointer to the located wide-character
or a null pointer if the wide-character does not occur in the object.
- wmemcmp()
The
wmemcmp()
function compares the first
n
wide-characters of the object pointed to by
ws1
to the first
n
wide-characters of the object pointed to by
ws2.
The
wmemcmp()
function returns an integer greater than, equal to, or less than zero,
accordingly as the object pointed to by
ws1
is greater than, equal to, or less than the object pointed to by
ws2.
- wmemcpy()
The
wmemcpy()
function copies
n
wide-characters from the object pointed to by
ws2
to the object pointed to by
ws1.
The null wide-character and
wchar_t
values not corresponding to valid characters are not treated specially.
The
wmemcpy()
function returns the value of
ws1.
- wmemmove()
The
wmemmove()
function copies
n
wide-characters from the object pointed to by
ws2
to the object pointed to by
ws1.
Copying takes place as if the
n
wide-characters from the object pointed to by
ws2
are first copied into a temporary array of
n
wide-characters that does not overlap the objects pointed to by
ws1
or
ws2,
and then the
n
wide-characters from the temporary array are copied into the object pointed
to by
ws1.
The
wmemmove()
function returns the value of
ws1.
- wmemset()
The
wmemset()
function copies the value of
wc
into each of the first
n
wide-characters of the object pointed to by
ws.
The
wmemset()
function returns the value of
ws.
APPLICATION USAGE
The prototypes of these functions are available to applications
if they are:
- a.
c99
conformant.
- b.
Compiled with
-D_XOPEN_SOURCE
macro with a value >= 500.
- c.
Compiled with
-D_POSIX_C_SOURCE
macro with a value >= 200112.
ERRORS
No errors are defined.
AUTHOR
wmemchr(),
wmemcmp(),
wmemcpy(),
wmemmove(),
wmemset()
were developed by HP and Mitsubishi Electric Corp.
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