WCSTOK(P) POSIX Programmer's Manual WCSTOK(P)
wcstok - split a wide-character string into tokens
wchar_t *wcstok(wchar_t *restrict ws1, const wchar_t *restrict ws2,
wchar_t **restrict ptr);
A sequence of calls to wcstok() shall break the wide-character string pointed to by ws1
into a sequence of tokens, each of which shall be delimited by a wide-character code from
the wide-character string pointed to by ws2. The ptr argument points to a caller-provided
wchar_t pointer into which the wcstok() function shall store information necessary for it
to continue scanning the same wide-character string.
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 shall search 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() shall return a null pointer. If
such a wide-character code is found, it shall be the start of the first token.
The wcstok() function shall then search from there for a wide-character code that is con-
tained in the current separator string. If no such wide-character code is found, the cur-
rent token extends to the end of the wide-character string pointed to by ws1, and subse-
quent searches for a token shall return a null pointer. If such a wide-character code is
found, it shall be overwritten by a null wide character, which terminates the current
token. The wcstok() function shall save a pointer to the following wide-character code,
from which the next search for a token shall start.
Each subsequent call, with a null pointer as the value of the first argument, shall start
searching from the saved pointer and behave as described above.
The implementation shall behave as if no function calls wcstok().
Upon successful completion, the wcstok() function shall return a pointer to the first
wide-character code of a token. Otherwise, if there is no token, wcstok() shall return a
No errors are defined.
The following sections are informative.
The Base Definitions volume of IEEE Std 1003.1-2001, <wchar.h>
Portions of this text are reprinted and reproduced in electronic form from IEEE Std
1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System
Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by
the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and The Open Group
Standard, the original IEEE and The Open Group Standard is the referee document. The orig-
inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .
IEEE/The Open Group 2003 WCSTOK(P)