wcsspn man page


This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

wcsspn — get the length of a wide substring


#include <wchar.h>

size_t wcsspn(const wchar_t *ws1, const wchar_t *ws2);


The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1‐2008 defers to the ISO C standard.

The wcsspn() function shall compute the length (in wide characters) 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.

Return Value

The wcsspn() function shall return the length of the initial substring of ws1; no return value is reserved to indicate an error.


No errors are defined.

The following sections are informative.

See Also


The Base Definitions volume of POSIX.1‐2008, <wchar.h>