WCSTRING(3C) Standard C Library Functions WCSTRING(3C)
NAME
wcstring, wcscat, wscat, wcsncat, wsncat, wcscmp, wscmp, wcsncmp,
wsncmp, wcscpy, wscpy, wcsncpy, wsncpy, wslen, wcschr, wschr,
wcsrchr, wsrchr, windex, wrindex, wcspbrk, wspbrk, wcswcs, wcsspn,
wsspn, wcscspn, wscspn, wcstok, wstok - wide-character string
operations
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);
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 following,
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-
character 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-character 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 indicate 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
difference between the values of the first pair of wide-character
codes that differ in the objects being compared. Upon completion,
both functions 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-
character 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-
character 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-character string that is shorter than
n wide-character
codes, null wide-character 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.
wslen() The
wslen() function computes the number of wide-character codes in
the wide-character string to which
ws points, not including the
terminating null wide-character code. It returns
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 terminating 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-
character 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 completion, 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-
character string pointed to by
ws1 of the sequence of wide-character
codes (excluding the terminating null wide-character code) in the
wide-character string pointed to by
ws2. Upon successful completion,
the function 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 initial 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
continue scanning the same wide-character string. This argument is
not available with the XPG4 and SUS versions of
wcstok(), nor is it
available with the
wstok() function. See
standards(7).
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
separator 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 contained 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-character 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(7) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|CSI | Enabled |
+--------------------+-----------------+
|Interface Stability | See NOTES. |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+
SEE ALSO
malloc(3C),
string(3C),
wcscasecmp(3C),
wcsdup(3C),
wcslen(3C),
wcswidth(3C),
wcwidth(3C),
attributes(7),
standards(7)NOTES
The
wcscat(),
wcsncat(),
wcscmp(),
wcsncmp(),
wcscpy(),
wcsncpy(),
wcschr(),
wcsrchr(),
wcspbrk(),
wcswcs(),
wcsspn(),
wcscspn(), and
wcstok() functions are Standard. The
wscat(),
wsncat(),
wscmp(),
wsncmp(),
wscpy(),
wsncpy(),
wslen(),
wschr(),
wsrchr(),
wspbrk(),
wsspn(),
wstok(),
windex(), and
wrindex() functions are Stable.
August 15, 2014 WCSTRING(3C)