wcstring(3C) Standard C Library Functions wcstring(3C)NAME
wcstring, wcscat, wscat, wcsncat, wsncat, wcscmp, wscmp, wcsncmp,
wsncmp, wcscpy, wscpy, wcsncpy, wsncpy, wcslen, wslen, wcschr, wschr,
wcsrchr, wsrchr, windex, wrindex, wcspbrk, wspbrk, wcswcs, wcsspn,
wsspn, wcscspn, wscspn, wcstok, wstok - wide-character string opera‐
tions
SYNOPSIS
#include <wchar.h>
wchar_t *wcscat(wchar_t *ws1, const wchar_t *ws2);
wchar_t *wcsncat(wchar_t *restrict ws1, const wchar_t *restrict ws2,
size_t n);
int wcscmp(const wchar_t *ws1, const wchar_t *ws2);
int wcsncmp(const wchar_t *ws1, const wchar_t *ws2, size_t n);
wchar_t *wcscpy(wchar_t *ws1, const wchar_t *ws2);
wchar_t *wcsncpy(wchar_t *restrict ws1, const wchar_t *restrict ws2,
size_t n);
size_t wcslen(const wchar_t *ws);
wchar_t *wcschr(const wchar_t *ws, wchar_t wc);
wchar_t *wcsrchr(const wchar_t *ws, wchar_t wc);
wchar_t *wcspbrk(const wchar_t *ws1, const wchar_t *ws2);
wchar_t *wcswcs(const wchar_t *ws1, const wchar_t *ws2);
size_t wcsspn(const wchar_t *ws1, const wchar_t *ws2);
size_t wcscspn(const wchar_t *ws1, const wchar_t *ws2);
XPG4, SUS, SUSv2, SUSv3
wchar_t *wcstok(wchar_t *restrict ws1, const wchar_t *restrict ws2);
Default and other standards
wchar_t *wcstok(wchar_t *ws1, const wchar_t *ws2, wchar_t **ptr);
#include <widec.h>
wchar_t *wscat(wchar_t *ws1, const wchar_t *ws2);
wchar_t *wsncat(wchar_t *ws1, const wchar_t *ws2, size_t n);
int wscmp(const wchar_t *ws1, const wchar_t *ws2);
int wsncmp(const wchar_t *ws1, const wchar_t *ws2, size_t n);
wchar_t *wscpy(wchar_t *ws1, const wchar_t *ws2);
wchar_t *wsncpy(wchar_t *ws1, const wchar_t *ws2, size_t n);
size_t wslen(const wchar_t *ws);
wchar_t *wschr(const wchar_t *ws, wchat_t wc);
wchar_t *wsrchr(const wchar_t *ws, wchat_t wc);
wchar_t *wspbrk(const wchar_t *ws1, const wchar_t *ws2);
size_t wsspn(const wchar_t *ws1, const wchar_t *ws2);
size_t wscspn(const wchar_t *ws1, const wchar_t *ws2);
wchar_t *wstok(wchar_t *ws1, const wchar_t *ws2);
wchar_t *windex(const wchar_t *ws, wchar_t wc);
wchar_t *wrindex(const wchar_t *ws, wchar_t wc);
ISO C++
#include <wchar.h>
const wchar_t *wcschr(const wchar_t *ws, wchar_t wc);
const wchar_t *wcspbrk(const wchar_t *ws1, const wchar_t *ws2);
const wchar_t *wcsrchr(const wchar_t *ws, wchar_t wc);
#include <cwchar>
wchar_t *std::wcschr(wchar_t *ws, wchar_t wc);
wchar_t *std::wcspbrk(wchar_t *ws1, const wchar_t *ws2);
wchar_t *std::wcsrchr(wchar_t *ws, wchar_t wc);
DESCRIPTION
These functions operate on wide-character strings terminated by wchar_t
NULL characters. During appending or copying, these routines do not
check for an overflow condition of the receiving string. In the follow‐
ing, ws, ws1, and ws2 point to wide-character strings terminated by a
wchar_t NULL.
wcscat(), wscat()
The wcscat() and wscat() functions append a copy of the wide-character
string pointed to by ws2 (including the terminating null wide-character
code) to the end of the wide-character string pointed to by ws1. The
initial wide-character code of ws2 overwrites the null wide-character
code at the end of ws1. If copying takes place between objects that
overlap, the behavior is undefined. Both functions return s1; no return
value is reserved to indicate an error.
wcsncat(), wsncat()
The wcsncat() and wsncat() functions append not more than n wide-char‐
acter codes (a null wide-character code and wide-character codes that
follow it are not appended) from the array pointed to by ws2 to the end
of the wide-character string pointed to by ws1. The initial wide-char‐
acter code of ws2 overwrites the null wide-character code at the end of
ws1. A terminating null wide-character code is always appended to the
result. Both functions return ws1; no return value is reserved to indi‐
cate an error.
wcscmp(), wscmp()
The wcscmp() and wscmp() functions compare the wide-character string
pointed to by ws1 to the wide-character string pointed to by ws2. The
sign of a non-zero return value is determined by the sign of the dif‐
ference between the values of the first pair of wide-character codes
that differ in the objects being compared. Upon completion, both func‐
tions return an integer greater than, equal to, or less than zero, if
the wide-character string pointed to by ws1 is greater than, equal to,
or less than the wide-character string pointed to by ws2.
wcsncmp(), wsncmp()
The wcsncmp() and wsncmp() functions compare not more than n wide-char‐
acter codes (wide-character codes that follow a null wide character
code are not compared) from the array pointed to by ws1 to the array
pointed to by ws2. The sign of a non-zero return value is determined by
the sign of the difference between the values of the first pair of
wide-character codes that differ in the objects being compared. Upon
successful completion, both functions return an integer greater than,
equal to, or less than zero, if the possibly null-terminated array
pointed to by ws1 is greater than, equal to, or less than the possibly
null-terminated array pointed to by ws2.
wcscpy(), wscpy()
The wcscpy() and wscpy() functions copy the wide-character string
pointed to by ws2 (including the terminating null wide-character code)
into the array pointed to by ws1. If copying takes place between
objects that overlap, the behavior is undefined. Both functions return
ws1; no return value is reserved to indicate an error.
wcsncpy(), wsncpy()
The wcsncpy() and wsncpy() functions copy not more than n wide-charac‐
ter codes (wide-character codes that follow a null wide character code
are not copied) from the array pointed to by ws2 to the array pointed
to by ws1. If copying takes place between objects that overlap, the
behavior is undefined. If the array pointed to by ws2 is a wide-charac‐
ter string that is shorter than n wide-character codes, null wide-char‐
acter codes are appended to the copy in the array pointed to by ws1,
until a total n wide-character codes are written. Both functions return
ws1; no return value is reserved to indicate an error.
wcslen(), wslen()
The wcslen() and wslen() functions compute the number of wide-character
codes in the wide-character string to which ws points, not including
the terminating null wide-character code. Both functions return ws; no
return value is reserved to indicate an error.
wcschr(), wschr()
The wcschr() and wschr() functions locate the first occurrence of wc in
the wide-character string pointed to by ws. The value of wc must be a
character representable as a type wchar_t and must be a wide-character
code corresponding to a valid character in the current locale. The ter‐
minating null wide-character code is considered to be part of the wide-
character string. Upon completion, both functions return a pointer to
the wide-character code, or a null pointer if the wide-character code
is not found.
wcsrchr(), wsrchr()
The wcsrchr() and wsrchr() functions locate the last occurrence of wc
in the wide-character string pointed to by ws. The value of wc must be
a character representable as a type wchar_t and must be a wide-charac‐
ter code corresponding to a valid character in the current locale. The
terminating null wide-character code is considered to be part of the
wide-character string. Upon successful completion, both functions
return a pointer to the wide-character code, or a null pointer if wc
does not occur in the wide-character string.
windex(), wrindex()
The windex() and wrindex() functions behave the same as wschr() and
wsrchr(), respectively.
wcspbrk(), wspbrk()
The wcspbrk() and wspbrk() functions locate the first occurrence in the
wide character string pointed to by ws1 of any wide-character code from
the wide-character string pointed to by ws2. Upon successful comple‐
tion, the function returns a pointer to the wide-character code, or a
null pointer if no wide-character code from ws2 occurs in ws1.
wcswcs()
The wcswcs() function locates the first occurrence in the wide-charac‐
ter string pointed to by ws1 of the sequence of wide-character codes
(excluding the terminating null wide-character code) in the wide-char‐
acter string pointed to by ws2. Upon successful completion, the func‐
tion returns a pointer to the located wide-character string, or a null
pointer if the wide-character string is not found. If ws2 points to a
wide-character string with zero length, the function returns ws1.
wcsspn(), wsspn()
The wcsspn() and wsspn() functions compute the length of the maximum
initial segment of the wide-character string pointed to by ws1 which
consists entirely of wide-character codes from the wide-character
string pointed to by ws2. Both functions return the length ws1; no
return value is reserved to indicate an error.
wcscspn(), wscspn()
The wcscspn() and wscspn() functions compute the length of the maximum
initial segment of the wide-character string pointed to by ws1 which
consists entirely of wide-character codes not from the wide-character
string pointed to by ws2. Both functions return the length of the ini‐
tial substring of ws1; no return value is reserved to indicate an
error.
wcstok(), wstok()
A sequence of calls to the wcstok() and wstok() functions break the
wide-character string pointed to by ws1 into a sequence of tokens, each
of which is delimited by a wide-character code from the wide-character
string pointed to by ws2.
Default and other standards
The third argument points to a caller-provided wchar_t pointer into
which the wcstok() function stores information necessary for it to con‐
tinue scanning the same wide-character string. This argument is not
available with the XPG4 and SUS versions of wcstok(), nor is it avail‐
able with the wstok() function. See standards(5).
The first call in the sequence has ws1 as its first argument, and is
followed by calls with a null pointer as their first argument. The sep‐
arator string pointed to by ws2 may be different from call to call.
The first call in the sequence searches the wide-character string
pointed to by ws1 for the first wide-character code that is not con‐
tained in the current separator string pointed to by ws2. If no such
wide-character code is found, then there are no tokens in the wide-
character string pointed to by ws1, and wcstok() and wstok() return a
null pointer. If such a wide-character code is found, it is the start
of the first token.
The wcstok() and wstok() functions then search from that point for a
wide-character code that is contained in the current separator string.
If no such wide-character code is found, the current token extends to
the end of the wide-character string pointed to by ws1, and subsequent
searches for a token will return a null pointer. If such a wide-charac‐
ter code is found, it is overwritten by a null wide character, which
terminates the current token. The wcstok() and wstok() functions save a
pointer to the following wide-character code, from which the next
search for a token will start.
Each subsequent call, with a null pointer as the value of the first
argument, starts searching from the saved pointer and behaves as
described above.
Upon successful completion, both functions return a pointer to the
first wide-character code of a token. Otherwise, if there is no token,
a null pointer is returned.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│CSI │Enabled │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │See NOTES. │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOmalloc(3C), string(3C), wcswidth(3C), wcwidth(3C), attributes(5), stan‐
dards(5)NOTES
The wcscat(), wcsncat(), wcscmp(), wcsncmp(), wcscpy(), wcsncpy(),
wcslen(), wcschr(), wcsrchr(), wcspbrk(), wcswcs(), wcsspn(), wcsc‐
spn(), and wcstok() functions are Standard. The wscat(), wsncat(),
wscmp(), wsncmp(), wscpy(), wsncpy(), wslen(), wschr(), wsrchr(), wsp‐
brk(), wsspn(), wstok(), windex(), and wrindex() functions are Stable.
SunOS 5.10 14 Aug 2002 wcstring(3C)