Querying DS_LICENSE gave me most of what I was looking for, but it wasn't obvious how many of the 16 DataStage thought was actually in use. Running 'dslictool' from the command line gave me this output:
$ ./bin/dslictool
Standard License is in effect.
Message[PIN0037]
8 CPU's licensed.
DSSRV package licensed.
No. Pid, Package Device name IP address Device sub-key
0 license seats are in use.
8 license seats are available.
What 'license seats' is it referring to here? All 16 were in use, not zero and none were available, hence the question.

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