snreddy_gopu:

And your question is....?

...roboticus

When your only tool is a hammer, all problems look like your thumb.

I think you want piped open:

open my $fh, "| ./setup.sh" or die $!;

# print $fh "$_\n" for qw(a b c ...);
[download]

When you then say print $fh ..., the shell script gets the data on stdin, as it would from your current heredoc.