I often find the need to open a fairly large number of input files simultaneously, to run line-by-line comparisons on them. I can not read in all of the complete files before starting my analysis - due to the large size the files, that would be a very slow and RAM-intensive approach.

The way I'm doing this now is horribly clumsy. I have an array of input file names, and then I have an array of arbitrary file handles, with at least as many elements as the former array, e.g.:

my @FileHandles = ('A', 'B', 'C'...'X');

I have a loop that opens all input files. Then to start reading them: 
$file1 = $InHandles[0];
while (<$file1>){
...
  for ($f = 1; $f < @InHandles; $f++){
    $file = $InHandles[$f];
    $_ = (<$file>);
...

[download]
where "..." includes the retrieval of information from the current line of each file.

Today I found a need to read in over 100 files, and this has motivated me to find a more sensible way to deal with large numbers of concurrently used file handles. Is there a simple way to generate unique handles automatically for each element in my array of input files, without typing out a silly array like the @FileHandles shown above?

I've also found that at least when using double letter file handles from an array, I am forced to turn off 'use strict', which I otherwise keep on to catch typos.

Thanks for any help you can offer.

In reply to File handles - there must be a better way by Anonymous Monk

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