void gtk_accel_group_lock ( GtkAccelGroup* accel_group )
Locks the given accelerator group.
Locking an acelerator group prevents the accelerators contained
within it to be changed during runtime. Refer to
gtk_accel_map_change_entry() about runtime accelerator changes.
If called more than once,
accel_group remains locked until
gtk_accel_group_unlock() has been called an equivalent number