need to process the file line by line. I originally had something like this: 
...

foreach $line (<FILE>) #main loop
{

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foreach works on lists so it reads the entire file into a list in memory and then iterates through the list.    To properly read just one line at a time you need to use a while loop instead: 

while ( my $line = <FILE> ) #main loop
{

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I am guessing that the while(<>) takes from @ARGV and not the values that I pass into the function

Yes, this is coorect.    The <> operator is special in that it reads through all the files in @ARGV and each file name is removed from @ARGV and put into $ARGV while that file is being processed.

In reply to Re: Efficiently processing a file by jwkrahn
in thread Efficiently processing a file by Anonymous Monk

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