vfwprintf - Man Page

wide-character formatted output of a stdarg argument list


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 <stdarg.h>
#include <stdio.h>
#include <wchar.h>

int vfwprintf(FILE *restrict stream, const wchar_t *restrict format,
    va_list arg);
int vswprintf(wchar_t *restrict ws, size_t n,
    const wchar_t *restrict format, va_list arg);
int vwprintf(const wchar_t *restrict format, va_list arg);


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 vfwprintf(), vswprintf(), and vwprintf() functions shall be equivalent to fwprintf(), swprintf(), and wprintf() respectively, except that instead of being called with a variable number of arguments, they are called with an argument list as defined by <stdarg.h>.

These functions shall not invoke the va_end macro. However, as these functions do invoke the va_arg macro, the value of ap after the return is unspecified.

Return Value

Refer to fwprintf().


Refer to fwprintf().

The following sections are informative.



Application Usage

Applications using these functions should call va_end(ap) afterwards to clean up.



Future Directions


See Also

Section 2.5, Standard I/O Streams, fwprintf()

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

Referenced By


2017 IEEE/The Open Group POSIX Programmer's Manual