How to use double buffering to avoid flicker. allegro game programming library.
#include <allegro.h>
Example exdbuf
This program demonstrates the use of double buffering. It moves a circle across the screen, first just erasing and redrawing directly to the screen, then with a double buffer.
BITMAP(3alleg4), END_OF_MAIN(3alleg4), SCREEN_H(3alleg4), SCREEN_W(3alleg4), acquire_screen(3alleg4), allegro_error(3alleg4), allegro_init(3alleg4), allegro_message(3alleg4), blit(3alleg4), circlefill(3alleg4), clear_keybuf(3alleg4), clear_to_color(3alleg4), create_bitmap(3alleg4), desktop_palette(3alleg4), destroy_bitmap(3alleg4), font(3alleg4), install_keyboard(3alleg4), install_timer(3alleg4), keypressed(3alleg4), makecol(3alleg4), release_screen(3alleg4), retrace_count(3alleg4), screen(3alleg4), set_gfx_mode(3alleg4), set_palette(3alleg4), textprintf_ex(3alleg4)