wcsspn - get length of a prefix wide-character substring

       For an explanation of the terms used in this section, see attributes(7).
       ┌─────────────────────────────────────────────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                                                                   │ Attribute     │ Value   │
       ├─────────────────────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │ wcsspn()                                                                    │ Thread safety │ MT-Safe │
       └─────────────────────────────────────────────────────────────────────────────┴───────────────┴─────────┘

       The  wcsspn()  function  is  the  wide-character equivalent of the strspn(3) function.  It determines the
       length of the longest initial segment of wcs which consists entirely of wide-characters listed in accept.
       In other words, it searches for the first occurrence in the wide-character string wcs of a wide-character
       not contained in the wide-character string accept.

       POSIX.1-2001, C99.

       Standard C library (libc, -lc)

       wcsspn - get length of a prefix wide-character substring

       The wcsspn() function returns the number of wide characters in the longest initial segment of  wcs  which
       consists  entirely  of  wide-characters listed in accept.  In other words, it returns the position of the
       first occurrence in the wide-character string wcs of a wide-character not contained in the wide-character
       string accept, or wcslen(wcs) if there is none.

strspn(3), wcscspn(3)

Linux man-pages 6.9.1                              2024-05-02                                          wcsspn(3)

       C11, POSIX.1-2008.

#include<wchar.h>size_twcsspn(constwchar_t*wcs,constwchar_t*accept);