strstrt

strstrt("string","key") searches for the character string "key" in "string" and returns the index to the first character of "key". If "key" is not found, it returns 0. Similar to C library function strstr except that it returns an index rather than a string pointer. strstrt("hayneedlestack","needle") = 4. This function is aware of utf8 encoding, so strstrt("αβγ","β") returns 2.