sorta ugly but it's ugly week ... you could try running the program with a choice of options that should produce known results. have you checked CPAN?

...
my $last_line = `tail $0 --lines=1`;
$last_line =~ /^the last line/ or die "non-functional tail";
...
__END__
the last line

[download]

or maybe '--version'.

In reply to Re: Verifiying an external program exists by zengargoyle
in thread Verifiying an external program exists by ibanix

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