#!/usr/bin/perl -w 
use strict;
die "Usage: $0 file1 file2\n"   unless  2 == @ARGV;
my($f1,$f2)=@ARGV; 
open(FILE1,"< $f1\0") or die "$!"; 
open(FILE2,"< $f2\0") or die "$!"; 
open(RESULT,">result") or die "$!"; 
while(  defined( $line1= <FILE1> )
   and  defined( $line2= <FILE2> )
) {
    print RESULT $line1, $line2;
}
if(  defined( $line1 )  ) {
    print RESULT $line1, <FILE1>;
} elsif(  defined( $line2 )  ) {
    print RESULT $line2, <FILE2>;
}
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        - tye (but my friends call me "Tye")