DOKK / manpages / debian 11 / libowfat-dev / str_rchr.3.en
str_rchr(3) Library Functions Manual str_rchr(3)

str_rchr - find character in ASCIIZ string

#include <str.h>

size_t str_rchr(const char* haystack,char needle);

str_rchr returns the index of the last occurrance of needle or the first occurrance of \0 in string.

strchr(3)