char *strchr(const char *s, int c);

       char *strrchr(const char *s, int c);
strchr returns a pointer to the first occurence of the character c in the string s. strrchr returns the last. Both return NULL if no match is found.

This str function is useful when you need to find that one, special character in a string - the first instance of it, mind you. Say, a delimeter, although strsep would be better for that. One possible use would be to clean out whitespace around a quoted string. The implementation of this is left as an exercise for the noder.