[tpm] Irritation problem

[arocker at Vex.Net]

Uri's pointed out the specific problems, but there's an additional point
to consider.

If you have the invoking script/.BAT file specify the config file as
redirected input, the OS should take care of any missing/misnamed files.
(I.e. perlprog < config.dat > results.txt) I believe even Windows'
brain-damaged shell can handle this. Then the Perl code doesn't have to do
anything beyond reading STDIN, and any error messages are standard OS
output that doesn't need special explanation.

The same idea applies to output.

An additional benefit is that when testing, it's easy to type stuff at the
program, and view the output directly, rather than having to create and
read files. (This may not apply if the input is long, complicated, and
static.)