Greetings,
Just a thought. 
#!/usr/bin/perl -w
use strict;
my %d = map{
        /^(\w+) /; 
        $1, $_;
    }grep{
        chomp;
        /^\w+ \d+/;
    }map{
        local @ARGV = ($_);
        <>;
    }<F*.dat>;
open(MRG, ">merge.dat") or die "Oops! There was a problem: $!";
print MRG, $d{$_}."\n" for(sort keys %d);
close MRG;

[download]
This assumes your input filenames match the pattern "F*.dat" for the glob to work on.

Updates

Thanks jdporter for the lower map suggestion. Much cleaner. Way better than the if(open (IN, $_)){#stuff} I was using.


BTW: we are Monks not Mongers :}

-InjunJoel
"I do not feel obliged to believe that the same God who endowed us with sense, reason and intellect has intended us to forego their use." -Galileo

In reply to Re: file merge problem by injunjoel
in thread file merge problem by Anonymous Monk

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