> Doesn't make it more sense to make this dependent from |DYN_DRV| ? If 
> the driver wasn't loaded from disk it isn't plausible to find a 
> meaningful |_oserror| value even if the target in general supports 
> |_oserror|, is it?


Fix, now dependend on DYN_DRV. Please note that this logic works for the 
current joystick drivers (and others), but
for example not for the Atari serial driver. The serial driver uses OS 
routines and the INSTALL function might set oserror.