$_ is a global variable. Your while is setting it to the last record of your filehandle and since your files end with a \n, $_ returns blank (I guess $_ gets set before the test is done to see if it has a value). Since this is Perl there is more than one way to get around this:

You can localize $_ in your sub like so: 

sub screwed {
  my ($in) = @_;

  local $_; # basically a temporary $_ just for this sub  

  open(IN, "<$in");
  while(<IN>) { print "file $in contains $_"; }
  close(IN);
}

[download]
Or you can set each line of the file to a variable in the while like so: 
while(defined(my $foo = <IN>)) { print "file $in contains $foo"; }

[download]

Hope that helps

Lobster Aliens Are attacking the world!

In reply to Re: opening a file destroys nulling entries in a list?!?! by cfreak
in thread opening a file destroys nulling entries in a list?!?! by matpalm

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