al_replace_path_component - Allegro 5 API

       Replace  the  i’th  directory  component by another string.  If the index is negative then count from the
       right, i.e. -1 refers to the last path component.  It is an error to  pass  an  index  which  is  out  of
       bounds.

       al_replace_path_component - Allegro 5 API

al_insert_path_component(3alleg5), al_remove_path_component(3alleg5)

Allegro reference manual                                                      al_replace_path_component(3alleg5)

              #include <allegro5/allegro.h>

              void al_replace_path_component(ALLEGRO_PATH *path, int i, const char *s)