Okay, here's something I don't understand.

Suppose I have the following code, I'll call it prog.pl:

#!/usr/bin/perl

my $lines;
my @lines;

print ("\@ARGV: @ARGV, \$\#ARGV: $#ARGV\n");

if (!@ARGV){
   print("No command line parameters present");
}

chomp(@lines = <>);

foreach $lines (@lines){
   print("$lines\n");
}

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1. If I run the program as perl prog.pl test.txt it prints out

@ARGV: test.txt, $#ARGV: 0

2. If I run the program as perl prog.pl it prints out

@ARGV: , $#ARGV: -1

(This next one is my problem.)

3. If I run the program as perl prog.pl < test.txt it prints out

@ARGV: , $#ARGV: -1

which looks as if there were no command line arguments.

Now, I realize that in some aspects, this might be considered correct,
as there are no command line arguments, just input to the <> operator.
Will GetOpt get around this peculiarity?
Or am I going to be stuck always showing my little help text no matter what?

Am I missing something dreadfully obvious?

In reply to Re: Testing <> for undefined by jdavidboyd
in thread Testing <> for undefined by kayak9630

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