- size_t l = strlen(fmt), i;
- wchar_t fmt2[l+1];
- rctx_t r = { s_read, (void *)s, 0, isspace };
- for (i=0; i<=l; i++) fmt2[i] = (unsigned char)fmt[i];
- return __scanf(&r, fmt2, ap);
+ FILE f = {
+ .buf = (void *)s, .cookie = (void *)s,
+ .read = do_read, .lock = -1
+ };
+ return vfscanf(&f, fmt, ap);