Provided by: manpages-posix-dev_2017a-2_all 

PROLOG
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.
NAME
wcslen, wcsnlen — get length of a fixed-sized wide-character string
SYNOPSIS
#include <wchar.h>
size_t wcslen(const wchar_t *ws);
size_t wcsnlen(const wchar_t *ws, size_t maxlen);
DESCRIPTION
For wcslen(): 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.1‐2017 defers to the ISO C standard.
The wcslen() function shall compute the number of wide-character codes in the wide-character string to
which ws points, not including the terminating null wide-character code.
The wcsnlen() function shall compute the smaller of the number of wide characters in the array to which
ws points, not including any terminating null wide-character code, and the value of maxlen. The
wcsnlen() function shall never examine more than the first maxlen characters of the wide-character array
pointed to by ws.
RETURN VALUE
The wcslen() function shall return the length of ws.
The wcsnlen() function shall return the number of wide characters preceding the first null wide-character
code in the array to which ws points, if ws contains a null wide-character code within the first maxlen
wide characters; otherwise, it shall return maxlen.
No return values are reserved to indicate an error.
ERRORS
No errors are defined.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
strlen()
The Base Definitions volume of POSIX.1‐2017, <wchar.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard
for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition, Copyright (C) 2018 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 original Standard can be obtained online at http://www.opengroup.org/unix/online.html .
Any typographical or formatting errors that appear in this page are most likely to have been introduced
during the conversion of the source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2017 WCSLEN(3POSIX)