The util_is_url function checks whether a string is a URL, returns 1 if the string is a URL and 0 otherwise. The string is a URL if it begins with alphabetic characters followed by a colon (:).
int util_is_url(char *url);
1 if the string specified by url is a URL, or 0 if the string specified by url is not a URL.
char *url is the string to be examined.