r = HaveVolume(vol$)
vol$is currently available. This is especially useful on AmigaOS and compatible systems because it will suppress the "Please insert volume XXX into any drive" system requester that usually pops up on AmigaOS systems when trying to access non-existent volumes. By checking the existence of the volume using this command first, you can easily get rid of the annoying requester on AmigaOS.
Trueif volume exists,
Print(HaveVolume("FOOBAR:"))The code above should return 0 because the specified typically doesn't exist. On AmigaOS, there will be no system requester asking for volume "FOOBAR:" if you use this code.