void xcb_change_gc_single(xcb_connection_t *conn, xcb_gcontext_t gc, uint32_t mask, uint32_t value);
uint32_t get_colorpixel(xcb_connection_t *conn, char *hex);
uint32_t get_mod_mask(xcb_connection_t *conn, uint32_t keycode);
xcb_window_t open_input_window(xcb_connection_t *conn, uint32_t width, uint32_t height);
int get_font_id(xcb_connection_t *conn, char *pattern, int *font_height);