I've been working with Perl for a few months now and have found this site to be extremely helpful. I like working with STDIN so that I can make scripts that interact with the cmd prompt. I have a very simple problem I'm trying to solve. When I use something like this... 
while (<STDIN>) {
    chomp;
    print "$_\n";
}

[download]
...it does the job. But it isn't smart enough to prompt me if I forget to pipe a file into it. I'd really like some suggestions about how to check if piped data is waiting from STDIN so that I can prompt when it hasn't been called properly.

In reply to Need help working with STDIN by Zio

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