A good learning process it to write a 'bad' or incomplete translator. Just going through and

TMP="/tmp/cas.$$.out"
to:
$tmp = "/tmp/cas.$$.out"
[download]

is useful and trying to map if ... ] then to if ( ... ) [ (sorry I'm a ksh fool) can be quite useful both in learning and in moving some of your stuff. The hard parts will still need to be done by hand.

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