in reply to Testing <> for undefined
Okay, here's something I don't understand.
Suppose I have the following code, I'll call it prog.pl:
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?
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"); }
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?
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Re^2: Testing <> for undefined
by graff (Chancellor) on Jul 11, 2004 at 03:18 UTC | |
by jdavidboyd (Friar) on Jul 12, 2004 at 13:32 UTC |
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