Hi dear monks,

i've hundreds of big CSV files (~ 3 Go) and i need to read the 3rd field of the 2nd line of each file.
here is my naive approach for achieving this goal, and i would like to know if it's correct and how i can speed this up.

thanks by advance, 
# -- the type of the file can be found by checking if the value
# -- of the 3rd field of the 2nd line is a number
sub check_field {

    my ($file_name) = @_;

    open my $fh, "<$file_name" 
    or die "*** ERROR opening '$file_name': $!";

    my @fields;

    while (<$fh>) {

       if ($. == 2) {
           chomp;
           @fields = split /;/;
           die '*** ERROR number of fields !=4' unless @fields == 4;
           last;
       }

    }

    close($fh);

    return $fields[2] =~ /^\d+$/;
}

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In reply to advice for reading data from a file by Anonymous Monk

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