osx man page for rindex

RINDEX(3)						   BSD Library Functions Manual 						 RINDEX(3)

NAME
     rindex -- locate character in string

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <strings.h>

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

DESCRIPTION
     The rindex() function locates the last character matching c (converted to a char) in the null-terminated string s.

RETURN VALUES
     A pointer to the character is returned if it is found; otherwise, NULL is returned.  If c is '', rindex() locates the terminating ''.

SEE ALSO
     index(3), memchr(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strstr(3), strtok(3)

HISTORY
     A rindex() function appeared in Version 6 AT&T UNIX.  Its prototype existed previously in <string.h> before it was moved to <strings.h> for
     IEEE Std 1003.1-2001 (``POSIX.1'') compliance.

BSD
								   June 4, 1993 							       BSD