@defun string-search needle haystack &optional start-pos
Return the position of the first instance of @var{needle} in
@var{haystack}, both of which are strings. If @var{start-pos} is
-non-@code{nil}, start searching from that position in @var{needle}.
+non-@code{nil}, start searching from that position in @var{haystack}.
Return @code{nil} if no match was found.
This function only considers the characters in the strings when doing
the comparison; text properties are ignored. Matching is always