vfPrintfW_s()

int Chusov::String::vfPrintfW_s ( ::FILE *restrict  stream, const wchar_t *restrict  pszFormat, va_list  ap  )

noexcept

The function behaves identically to vfPrintfW but with some security enhancements.

Parameters

[in]	stream	is an output file stream to write to.
[in]	pszFormat	is a pointer to a zero terminated wide string defining how to interpret data, passed as additional parameters, during the construction of the output. See PrintfW_s for the definition of the format lexemes.
[in]	ap	is a variable argument list containing data used to construct an output string according to the format.

Returns

On success the function returns a number of characters of the output not counting the terminating zero. If an output, encoding or runtime constraint violation error occurs the function returns a negative value.

The function behaves identically to vfPrintfW except for the following explicit runtime constraints:

1. Neither stream not pszFormat is a NULL pointer.
2. The 'n' format type specifier is not allowed (modified or not by additional flags, width, precision, size).
3. Any pointer corresponding to the 's' or 'S' format type specifier must not be NULL.

If any of this constraints are violated the function will generate assertion and, if continue of execution is allowed, fail setting errno to EINVAL.

The function implements security enhancements for the vfPrintfW function just like vfwprintf_s function, defined in the ISO/IEC TR 24731-1 standard, provides the same enhancements for the C99 vfwprintf function.

See also

PrintfW_s;
vfPrintfW;
vfPrintfA_s.