freebsd man page for show_mouse

show_mouse(3alleg4)						  Allegro manual					       show_mouse(3alleg4)

NAME

       show_mouse - Tells Allegro to display a mouse pointer on the screen.

SYNOPSIS

       #include <allegro.h>

       void show_mouse(BITMAP *bmp);

DESCRIPTION

       Tells  Allegro to display a mouse pointer on the screen. This will only work if the timer module has been installed. The mouse pointer will
       be drawn onto the specified bitmap, which should normally be `screen' (see later for information about bitmaps). To hide the mouse pointer,
       call show_mouse(NULL).

       Warning:  if  you  draw anything onto the screen while the pointer is visible, a mouse movement interrupt could occur in the middle of your
       drawing operation. If this happens the mouse buffering and graphics drawing code will get confused and will  leave  'mouse  droppings'  all
       over  the  screen. To prevent this, you must make sure you turn off the mouse pointer whenever you draw onto the screen. This is not needed
       if you are using a hardware cursor.

       Note: you must not be showing a mouse pointer on a bitmap at the time that  the	bitmap	is  destroyed  with  destroy_bitmap(),	e.g.  call
       show_mouse(NULL); before destroying the bitmap. This does not apply to `screen' since you never destroy `screen' with destroy_bitmap().

SEE ALSO

       install_mouse(3alleg4),	install_timer(3alleg4),  set_mouse_sprite(3alleg4), scare_mouse(3alleg4), freeze_mouse_flag(3alleg4), show_os_cur-
       sor(3alleg4), exmouse(3alleg4), expal(3alleg4), exshade(3alleg4), exspline(3alleg4), exsyscur(3alleg4)

Allegro 							   version 4.4.2					       show_mouse(3alleg4)