While fixing a Nagios ntp script this afternoon, I encountered something odd. Here's the test script I reduced the behaviour to: 

#!/usr/bin/perl -w

use strict;

#  Test to see if $. really does break when reading from DATA.

{
  foreach (<DATA>) { print "Try line $.:$_"; }
}

__DATA__
This is line 1.
This is the second line.
Here is line 3.
The last line is line 4.

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When run, this produces 
[alex@foo bar]$ perl -w test2.pl 
Try line 4:This is line 1.
Try line 4:This is the second line.
Try line 4:Here is line 3.
Try line 4:The last line is line 4.

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except that I was expecting 
[alex@foo bar]$ perl -w test2.pl 
Try line 1:This is line 1.
Try line 2:This is the second line.
Try line 3:Here is line 3.
Try line 4:The last line is line 4.

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What's happening? Why isn't $. showing me the correct input line number for the data?

Alex / talexb / Toronto

"Groklaw is the open-source mentality applied to legal research" ~ Linus Torvalds

In reply to Odd behaviour with $. and <DATA> by talexb

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