I have a test program as shown below. When I pipe data to it, the output displays as expected. When I run the program stand-alone, it silently waits for input. I need a way to test for this condition and exit the program, but so far I can find none. Does anyone know a way of testing for this condition?

Here is the program which I named test.pl: 

#!/usr/bin/perl
use strict;
use warnings;
while( <> ) {
    print $_;
}

[download]

Note: I'm running on Windows, hence the use of "echo" below to pipe data.

Test #1:
echo a | test.pl (This works as expected)

Test #2:
test.pl (This silently waits for input. I need to test for this condition and exit the program)

"It's not how hard you work, it's how much you get done."

In reply to How to Test For Empty Piped Input by roho

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