iswblank
int iswblank(wint_t);
{ "blank", iswblank },
while (--i >= 0 && !iswblank(buf[i]))
while (iswblank(*s) && s < end)
while (iswblank(*s) && s < end)
while (src < end && iswblank(*src))
if (iswalnum(c) || iswblank(c)) {
while (start < BWSLEN(s) && iswblank(BWS_GET(s,start)))
isblank = iswblank(BWS_GET(s, cpos));
while (iswblank(bws_get_iter_value(s)))
while (iswblank(*str))
while (*str != L'\0' && !iswblank(*str))