Seems simple enough, loop through the first file and create a hash that contains the first column as the key and the second as the value. Next, loop through the second file and replace the second column with the appropriate value from the hash if it is found. Print the results out to the new file: 
use strict;

open FILE1, 'file1.txt' or die $!;
open FILE2, 'file2.txt' or die $!;
open NEW,   '>new.txt'  or die $!;

my %lookup;
while (<FILE1>) {
   my ($key,$id) = split(/\s*:\s*/,$_);
   $lookup{$key} = $id;
}

while (<FILE2>) {
   my @fields = split(/\s*:\s*/,$_);
   $fields[1] = $lookup{$fields[0]} || $fields[1];
   print NEW join(' :  ',@fields),"\n";
}

[download]

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: Problems getting a file with information of two diferent ones by jeffa
in thread Problems getting a file with information of two diferent ones by simonuca

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