Loads joystick calibration data.
Restores calibration data previously stored by save_joystick_data() or
the setup utility. This sets up all aspects of the joystick code: you
don't even need to call install_joystick() if you are using this
function. Pass a NULL filename to read the data from the currently
selected configuration file.
Returns zero on success: if it fails the joystick state is undefined and
you must reinitialise it from scratch.
The following projects include source code containing this keyword: