mbstowcs
[minimal multibyte string to wide char converter]

SYNOPSIS
#include <stdlib.h>
int mbstowcs(wchar_t *pwc, const char *s, size_t n);

DESCRIPTION
When MB_CAPABLE is not defined, this is a minimal ANSI-conforming implementation of mbstowcs. In this case, the only multibyte character sequences recognized are single bytes, and they are converted to wide-char versions simply by byte extension.

When MB_CAPABLE is defined, this routine calls _mbstowcs_r to perform the conversion, passing a state variable to allow state dependent decoding. The result is based on the locale setting which may be restricted to a defined set of locales.

RETURNS
This implementation of mbstowcs returns 0 if s is NULL or is the empty string; it returns -1 if MB_CAPABLE and one of the multibyte characters is invalid or incomplete; otherwise it returns the minimum of n (or the number of multibyte characters in s plus 1—to compensate for the NULL character). If the return value is -1, the state of the pwc string is indeterminate. If the input has a length of 0, the output string will be modified to contain a wchar_t NULL terminator.

COMPLIANCE
mbstowcs is required in the ANSI C standard. However, the precise effects vary with the locale.

mbstowcs requires no supporting OS subroutines.