+#include <_PDCLIB_io.h>
+
+int vfscanf_unlocked( FILE * _PDCLIB_restrict stream,
+ const char * _PDCLIB_restrict format,
+ va_list arg )
+{
+ /* TODO: This function should interpret format as multibyte characters. */
+ struct _PDCLIB_status_t status;
+ status.base = 0;
+ status.flags = 0;
+ status.n = 0;
+ status.i = 0;
+ status.current = 0;
+ status.s = NULL;
+ status.width = 0;
+ status.prec = 0;
+ status.stream = stream;
+ va_copy( status.arg, arg );
+
+ while ( *format != '\0' )
+ {
+ const char * rc;
+ if ( ( *format != '%' ) || ( ( rc = _PDCLIB_scan( format, &status ) ) == format ) )
+ {
+ int c;
+ /* No conversion specifier, match verbatim */
+ if ( isspace( *format ) )
+ {
+ /* Whitespace char in format string: Skip all whitespaces */
+ /* No whitespaces in input does not result in matching error */
+ while ( isspace( c = getc( stream ) ) )
+ {
+ ++status.i;
+ }
+ if ( ! feof( stream ) )
+ {
+ ungetc( c, stream );
+ }
+ }
+ else
+ {
+ /* Non-whitespace char in format string: Match verbatim */
+ if ( ( ( c = getc( stream ) ) != *format ) || feof( stream ) )
+ {
+ /* Matching error */
+ if ( ! feof( stream ) && ! ferror( stream ) )
+ {
+ ungetc( c, stream );
+ }
+ else if ( status.n == 0 )
+ {
+ return EOF;
+ }
+ return status.n;
+ }
+ else
+ {
+ ++status.i;
+ }
+ }
+ ++format;
+ }
+ else
+ {
+ /* NULL return code indicates matching error */
+ if ( rc == NULL )
+ {
+ break;
+ }
+ /* Continue parsing after conversion specifier */
+ format = rc;
+ }
+ }
+ va_end( status.arg );
+ return status.n;
+}