Greetings, it has been quite a while since I posted a question, but I've been lurking always reading the wisdom contained herein.

My question is this: I have 2 text files. Each one looks like something one would see when they cat /etc/passwd. The first file (I'll call it file1) has a list of users that need accounts. The second file has a list (in /etc/passwd format) of current accounts.

I easily created a list of users that *need* accounts by simple shell looping and grep. I was also able to produce a list of duplicate users easily enough via the shell again.

Alas, the last thing i wanted to do was to show who was left. These would be the accounts that have to be deleted. When simple shell one liners were of no avail, I turned to my swiss army knife of text processing, but I must admit that I am thwarted by this seemingly simple task.

Could I have just edited the files side by side? I could have, but I thought I was cheating myself out of an opportunity to learn something. And I here I am. I have code that I will paste below with copious comments as to what I think I should do, but what ultimately escapes me.

In my defense I will say one thing. I am not a programmer by trade, nor have I taken any programming courses outside of basic programming, and Pascal in high school.

#!/usr/bin/perl

use strict;

# Grep a user line OUT of a file, given a list of names, from another 
+file

# psuedo code:
# if file1 contains a name from file2, skip the line
# if file1 does NOT contain a name from file2, print the line.
#
# I am using this to determine a list of
# accounts that should be present, or not, on a server

my @users;
my $file1=$ARGV[0];
my $file2=$ARGV[1];

open FILE1, "<$file1" or die "Cannot open $file1: $!\n";
my @file1=<FILE1>;
close FILE1;

open FILE2, "<$file2" or die "Cannot open $file2: $!\n";
my @file2=<FILE2>;
close FILE2;
# Create @users array
my @out;
foreach my $line (@file2) {
  if ($line =~ /#/) {
    @out=split /\s+/,$line;
    push @users,$out[1];
  }
}

LINE: foreach my $line (@file1) {
  USER: foreach my $user (@users) {
    print "is $user on $line";
    if ($line =~ /$user/i) {
      print "YES $user is on $line ; next LINE\n";
      next LINE;
    } else {
      # This is where I get into trouble. I'm thinking I need to set
      # some kind of flag or something, because otherwise I will exhau
+st
      # the total list of users and will either get false positives
      # or skip them all together...
      print "nope... next USER\n";
      next USER;
    }
  }
}

[download]

Very funny Scotty... Now PLEASE beam down my PANTS!

In reply to Reconcile one list against another by spartan

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