A few comments:
1) get in the habit of using the Unix "hash bang" line (more portable code). Windows does not use the path at all - so might as well use the Unix path. BUT, Windows does pay attention to the flags, e.g. -w means "use warnings;".

2) code was a bit overly complicated - a possible re-formulation is below.

3) A positive comment: the way that you opened all the files at the beginning is a good idea. no need to do a whole bunch of work, only to find out later that for example you can't open the output file..

Code untested:

#!/usr/bin/perl -w
use strict;

my $FILE1 = "D:/Data/WES/File1.txt";  # You can use "/"
my $FILE2 = "D:/Data/WES/File2.txt";  # avoids this \\ stuff
my $FILE3 = "D:/Data/WES/File3.txt";

open(F1,'<', $FILE1) or die "Can't open $FILE1\n";
open(F2,'<', $FILE2) or die "Can't open $FILE2\n";
open(F3,'>', $FILE3) or die "Can't open $FILE3\n";

#F3 header goes here

my %File2Parts;  # why call it F1parts? these numbers are
                 # coming from file 2. names matter.

while (my $PartNumber = <F2>) 
{
    chomp $PartNumber;
    next if $PartNumber =~ /^\s*$/;      # skip blank lines 
                              # often a "unseen" trailing blank line
                              # can cause troubles
    $File2Parts{$PartNumber} = 1;
}
    
close F2;

while (my $uline = <F1>) 
{
    chomp;  #you need this when splitting on other than white space
    
    my @ufields = split(/\|/, $uline);
        
    my ($PartNumber, $Std_Cost, $Last_Paid_Price,
        $Qty_In_Stock, $Moto_Preferred_Part, $Rev,
        $Agile_Description) = (@ufields)[0,1,2,3,7,9,10];
        
    if ($File2Parts{$PartNumber}) 
    {   
        print F3 "$PartNumber|$Std_Cost|$Last_Paid_Price|$Qty_In_Stock
+|$Moto_Preferred_Part|$Rev|$Agile_Description\n";
    }
}

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In reply to Re: Question on file compare by Marshall
in thread Question on file compare by sureshsmr

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