wcstok(3) Library Functions Manual wcstok(3)
NAME
wcstok - split wide-character string into tokens
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <wchar.h>
wchar_t *wcstok(wchar_t *restrict wcs, const wchar_t *restrict delim,
wchar_t **restrict ptr);
DESCRIPTION
The wcstok() function is the wide-character equivalent of the strtok(3)
function, with an added argument to make it multithread-safe. It can
be used to split a wide-character string wcs into tokens, where a token
is defined as a substring not containing any wide-characters from de-
lim.
The search starts at wcs, if wcs is not NULL, or at *ptr, if wcs is
NULL. First, any delimiter wide-characters are skipped, that is, the
pointer is advanced beyond any wide-characters which occur in delim.
If the end of the wide-character string is now reached, wcstok() re-
turns NULL, to indicate that no tokens were found, and stores an appro-
priate value in *ptr, so that subsequent calls to wcstok() will con-
tinue to return NULL. Otherwise, the wcstok() function recognizes the
beginning of a token and returns a pointer to it, but before doing
that, it zero-terminates the token by replacing the next wide-character
which occurs in delim with a null wide character (L'\0'), and it up-
dates *ptr so that subsequent calls will continue searching after the
end of recognized token.
RETURN VALUE
The wcstok() function returns a pointer to the next token, or NULL if
no further token was found.
ATTRIBUTES
For an explanation of the terms used in this section, see attrib-
utes(7).
┌───────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├───────────────────────────────────────────┼───────────────┼─────────┤
│ wcstok() │ Thread safety │ MT-Safe │
└───────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
C11, POSIX.1-2008.
HISTORY
POSIX.1-2001, C99.
NOTES
The original wcs wide-character string is destructively modified during
the operation.
EXAMPLES
The following code loops over the tokens contained in a wide-character
string.
wchar_t *wcs = ...;
wchar_t *token;
wchar_t *state;
for (token = wcstok(wcs, L" \t\n", &state);
token != NULL;
token = wcstok(NULL, L" \t\n", &state)) {
...
}
SEE ALSO
strtok(3), wcschr(3)
Linux man-pages 6.7 2023-10-31 wcstok(3)
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