al_get_render_state - Allegro 5 API

       Returns one of several render attributes; see ALLEGRO_RENDER_STATE(3alleg5) for details.

       This function will return -1 when there is no current display.

       al_get_render_state - Allegro 5 API

al_set_render_state(3alleg5),       ALLEGRO_RENDER_STATE(3alleg5),      ALLEGRO_RENDER_FUNCTION(3alleg5),
       ALLEGRO_WRITE_MASK_FLAGS(3alleg5)

Allegro reference manual                                                            al_get_render_state(3alleg5)

       5.2.10

              #include <allegro5/allegro.h>

              int al_get_render_state(ALLEGRO_RENDER_STATE state)