XkbSetDeviceButtonActions assigns actions to the buttons of the device specified in device_info->device_spec. Actions are assigned to num_buttons buttons beginning with first_button and are taken from the actions specified in device_info->btn_acts.
If the server does not support assignment of Xkb actions to extension device buttons, XkbSetDeviceButtonActions has no effect and returns False. If the device has no buttons or if first_button or num_buttons specify buttons outside of the valid range as determined by device_info->num_btns, the function has no effect and returns False. Otherwise, XkbSetDeviceButtonActions sends a request to the server to change the actions for the specified buttons and returns True.
If the actual request sent to the server involved illegal button numbers, a BadValue protocol error is generated. If an invalid device identifier is specified in device_info->device_spec, a BadKeyboard protocol error results. If the actual device specified in device_info->device_spec does not contain buttons and a request affecting buttons is made, a BadMatch protocol error is generated.