I have a file that contains a single integer number which is used as a counter. What I'd like to do is open the file, read the number, increment by 1, write the result to the original file for next time. Seems simple enough, but for the life of me I can't get it to work.

Any suggestions? The usual result is the file written is empty. I have tried so many different ways to do this, that I have really confused myself.... one version looks like the following (don't laugh) 

open (RECORD_NUMBER, "counter_data.dat") or die;
$count = <RECORD_NUMBER>;
$count = $count + 1;
print RECORD_NUMBER "$count";
close (RECORD_NUMBER) or die;

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In reply to File I/O by Anonymous Monk

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