XSetDeviceButtonMapping(), XGetDeviceButtonMapping() - query or change device button mappings
int XSetDeviceButtonMapping (Display *display, XDevice *device,
unsigned char map[], int nmap)
int XGetDeviceButtonMapping (Display *display, XDevice *device,
unsigned char map_return[], int nmap)
The XSetDeviceButtonMapping(3) request sets the mapping of the specified device. If it succeeds, the X server generates a DeviceMappingNotify event, and XSetDeviceButtonMapping(3) returns MappingSuccess. Element map[i] defines the logical button number for the physical button i+1. The length of the list must be the same as XGetDeviceButtonMapping(3) would return, or a BadValue error results. A zero element disables a button, and elements are not restricted in value by the number of physical buttons. However, no two elements can have the same nonzero value, or a BadValue error results. If any of the buttons to be altered are logically in the down state, XSetDeviceButtonMapping(3) returns MappingBusy, and the mapping is not changed.
XSetDeviceButtonMapping(3) can generate BadDevice, BadMatch, and BadValue errors.
The XGetDeviceButtonMapping(3) request returns the current mapping of the specified device. Buttons are numbered starting from one. XGetDeviceButtonMapping(3) returns the number of physical buttons actually on the device. The nominal mapping for a device is map[i]=i+1. The nmap argument specifies the length of the array where the device mapping is returned, and only the first nmap elements are returned in map_return.
XGetDeviceButtonMapping(3) can generate BadDevice or BadMatch errors.
Programming With Xlib