no command.
vsam, unlike db2, does not have 'triggers',
thus the best you can do is
only have one module that is CALLed
(in batch: dynamic would be best, but you can link it as static ..
in CICS you don't have that problem, as every thing should be dynamically linked,
but IMUO it would be best in CICS to execute a CICS LINK to the module)
that way, you would have only two modules that deal with i/o
and could control the number of records,
but then you have the problem of determining the current record count.
easiest way would to have a integer counter in each record
(which would be the primary part of the alt-index and only allow 1 thru 100.)
but, then you have the logical question that bubbles up from this
morass,
why do you only want 100 records?