int strrpos (string haystack, char needle)
Returns the numeric position of the last occurrence of needle in the haystack string. Note that the needle in this case can only be a single character. If a string is passed as the needle, then only the first character of that string will be used.
If needle is not found, returns false.
If needle is not a string, it is converted to an integer and applied as the ordinal value of a character.
See also strpos(), strrchr(), substr(), stristr(), and strstr().