> Is there a way to test whether a DEVCTRL command was
> successful?

I talked to the author just now.  He says that he doesn't explicitly
set JCW or CIERROR to indicate success or failure.  However, if the
I/O system returns an error to him, he will format the error message
and write it to $STDLIST.  Thus, you might be able to redirect the
output of DEVCTRL and scan for errors.  I asked him if it would be easy
to add the ability to detect the current device status (e.g. compression
is ON, etc.) to DEVCTRL and he replied "no".

  FYI,
  Jeff Vance, CSY

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