wcsftime - Man Page

convert date and time to a wide-character string


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.


#include <wchar.h>

size_t wcsftime(wchar_t *restrict wcs, size_t maxsize,
    const wchar_t *restrict format, const struct tm *restrict timeptr);


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 wcsftime() function shall be equivalent to the strftime() function, except that:


The argument wcs points to the initial element of an array of wide characters into which the generated output is to be placed.


The argument maxsize indicates the maximum number of wide characters to be placed in the output array.


The argument format is a wide-character string and the conversion specifications are replaced by corresponding sequences of wide characters. It is unspecified whether an encoding error occurs if the format string contains wchar_t values that do not correspond to members of the character set of the current locale.


Field widths specify the number of wide characters instead of the number of bytes.


The return value indicates the number of wide characters placed in the output array.

If copying takes place between objects that overlap, the behavior is undefined.

Return Value

If the total number of resulting wide-character codes including the terminating null wide-character code is no more than maxsize, wcsftime() shall return the number of wide-character codes placed into the array pointed to by wcs, not including the terminating null wide-character code. Otherwise, zero is returned and the contents of the array are unspecified.


No errors are defined.

The following sections are informative.



Application Usage




Future Directions


See Also


The Base Definitions volume of POSIX.1-2017, <wchar.h>

Referenced By


2017 IEEE/The Open Group POSIX Programmer's Manual