my %passwd;
my %smbpasswd;

while (<PASSWD>)
{
    next if /^#/;
    chomp;
    my ($name, $uid) = (split ':', $_, 4)[0,2];
    $passwd{$uid} = $name;
}

# Do the same for SMBPASSWD, except use [0,1] instead of [0,2]

foreach my $uid (keys %passwd)
{
    unless (exists $smbpasswd($uid})
    {
        print "'$uid' in passwd, not in smbpasswd\n";
        next;
    }

    # Deleted to do later comparison
    my $smb_name = delete $smbpasswd{$uid};

    unless ($passwd{$uid} eq $smb_name)
    {
        print "$uid has $passwd{$uid} in passwd, but $smb_name in smbb
+passwd\n";
    }
}

while (my ($k, $v) = each %smbpasswd)
{
    print "$k in smbpasswd, not in passwd\n";
}
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Yes, dragonchild this is indeed the usual way. That's why I said it's what I had considered. What I am looking to see is whether that is the only reasonable (or practical) way or whether there is another, better, way using some technique I did not know or using some module(s) I had not found.

Parsing can be done using tilly's Text::xSV. Array::Compare might be useful in building the comparisons, as might Set::Scalar. Set::Scalar will allow you to generate two lists of UIDs and get the differences between the two. Then, you can do the same thing, but with the names from the acceptable UIDs.

Personally, I think that all these modules are overkill for what is, essentially, a one-off. But, that's just me. (Do you really anticipate your *passwd files getting out of sync again?? That sounds like a bigger issue, to me ...)

------
We are the carpenters and bricklayers of the Information Age.

The idea is a little like C++ templates, except not quite so brain-meltingly complicated. -- TheDamian, Exegesis 6

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.

use strict;
use DBI;
use DBD::CSV;
use IO::File;

# Prepare the csv file #1
my $p; { my $f = new IO::File "passwd", "r"; local $/; $p = <$f>; }
       { my $t = new IO::File "passwd.txt", "w";
         print $t uc("login:x:uid:gid:desc:home:shell\n"), $p; }

# Prepare the csv file #2
my $p; { my $f = new IO::File "passwd2", "r"; local $/; $p = <$f>; }
       { my $t = new IO::File "passwd2.txt", "w";
         print $t uc("login:x:uid:gid:desc:home:shell\n"), $p; }

# Connect to CSV database
my $dbh = DBI->connect("DBI:CSV:csv_sep_char=\\:") or die "Cannot conn
+ect: " . $DBI::errstr;
$dbh->{'csv_tables'}->{'passwd'}  = { 'file' => 'passwd.txt' };
$dbh->{'csv_tables'}->{'passwd2'} = { 'file' => 'passwd2.txt' };
my $sth = $dbh->prepare("SELECT p1.login FROM passwd p1, passwd2 p2
                        WHERE (p1.login=p2.login) AND (p1.uid=p2.uid)"
+);
$sth->execute();

# Get the matching id's
my $matched;
while (my $res = $sth->fetchrow_hashref())
{
    $matched .= ",'" . $res->{LOGIN} . "'";
}
$sth->finish;

# Get the unmatched id's in passwd2
$sth = $dbh->prepare("SELECT login FROM passwd2 WHERE login not in ("
                     .substr($matched, 1) . ")");
$sth->execute();
while (my $res = $sth->fetchrow_hashref())
{
    print "Unmatched accounts in passwd2: $res->{LOGIN}\n";
}
$sth->finish;

# Get the unmatched id's in passwd
$sth = $dbh->prepare("SELECT login FROM passwd WHERE login not in ("
                     .substr($matched, 1) . ")");
$sth->execute();
while (my $res = $sth->fetchrow_hashref())
{
    print "Unmatched accounts in passwd2: $res->{LOGIN}\n";
}

$dbh->disconnect;

unlink("passwd.txt", "passwd2.txt");
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