Your problem has been solved even before perl existed. 'paste' combines files in a column by column fashion. I'd use bits and pieces like these: 
my $command = 'paste ' . join(' ', @ARGV);
open FH, $command .'|';
while <FH> {
  @one_line = split "\t", $_;
  # do something
}

[download]
But I suspect that that your application needs something more efficient, as the presented solutions preseted up to now cause many disk seeks. Ignoring caches there is a seek for each line of each file!

I'd 'slurp' all files into an @array[file_no][line_no] one after another. This is done linear and at once. If the array does not fit into RAM, I'd use Tie::File. See e. g. http://www.sysarch.com/Perl/slurp_article.html

In reply to Re: Naming file handles with variables? by NiJo
in thread Naming file handles with variables? by sinee

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