How about some <> magic: 

#! /usr/bin/perl
#Call the scripts with <scriptname> passwd.*

while (<>) {
       ($login, $passwd, $uid, $gid,
        $gcos, $home, $shell) = split(/:/);
       $USERS{$login} = $gcos;
}

$nf="endo";
open (NEWFILE, ">$nf");
foreach $login (sort keys %USERS) {
       $gcos = $USERS{$login};
       print NEWFILE "$login, $gcos\n";
   }

[download]

Now just call the script with the passwd files as arguments(or even with passwd.*). The <> in the while will automatically open each file in turn and read it in for you. I also moved the opening of NEWFILE to the end of the script since that's when you actually have to have it open.

Later

In reply to Re: /etc/passwd by pzbagel
in thread Building data structure from several /etc/passwd files by tux242

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