I've seen many post about reading large files efficiently but has anyone experienced a error when trying to open a large file say (3 - 4 gigs)? The code below works fine on small files but when i try to parse a 3 - 4 gig file i get this error: readline() on closed filehandle main::IN at ./parse.pl line 11. 
#!/usr/bin/perl -w 

$| = 1;

$in_file = 'very_large_text_file'; 
$out_file = 'parsed_text_file';

open(IN, "<$in_file");
open(OUT, ">$out_file");

while(<IN>){
  ($email, $other) = split(/\s+/,$_); 
  print OUT "$email\n";
}

close(OUT);
close(IN);

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In reply to Parsing a 3 - 4 gig text file by Anonymous Monk

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