I am implemeting a GUI client running on HPUX-11 that has DAT saving functionality. Intermittently, I get a problem when trying to perform a DAT save. The first operation, performed before the actual save, is to rewind the DAT tape, this is done using "Runtime.getRuntime().exec("mt rewind");".

Now and then (maybe 1 in 15 times) this throws the following exception : IOException:
> java.io.IOException: ?????X?y?[?X???????????B
> at java.lang.UNIXProcess.forkAndExec(Native Method). Yes, I really do get all those ???X[ characters. Runtime has eventually called this UNIXProcess method that seems to be the problem - ether in forking the process or executing the command. Has anyone ever seen anything similar to this. The only exception being thrown is an IOException, so I can't narrow down my catch clause. Can anybody help with this.

Cheers.