#!/usr/bin/perl 
 
use warnings; 
use strict; 
 
my $user_grp = read_doc("/etc/passwd"); 
 
my %admin_menu = ( 
    1 => sub { 
        my $username = get_input("Enter username: "); 
        if ( exists $user_grp->{$username} ) { 
            print "\nUser ", $username, " exist!"; 
            return; 
        } 
 
        system( "useradd", "-u $$", "-g", "users", "$username" ); 
    }, 
    2 => sub { 
        my $username = get_input("Enter username: "); 
        if ( exists $user_grp->{$username} ) { 
 
            system( "userdel", "$username" ) 
              if get_input("Do you really want to remove the $username 
?: ") =~ 
              /\by\b/i; 
        } 
    }, 
 
    3 => sub { 
        my $group_name = get_input("Enter Group Name: "); 
        if ( exists $group_name->{$group_name} ) { 
            print "\nUser ", $group_name, " exist!"; 
            return; 
        } 
 
        system( "groupadd -g $group_id $group_name" ); 
    }, 
    4 => sub { 
        my $group_name = get_input("Enter Group Name: "); 
        if ( exists $group_name->{$group_name} ) { 
 
            system( "groupdel", "$group_name" ) 
              if get_input("Do you really want to remove the $group_na 
+me 
?: ") =~ 
              /\by\b/i; 
        } 
    }, 
 
    5 => sub { get_input("Exiting the Program\n"); exit(); }, 
); 
 
do { 
    admin_menu(); 
    $choice = get_input("Enter your choice: "); 
    if ( $choice < 1 or $choice > 5 ) { 
        admin_menu(); 
    } 
    else { $admin_menu{$choice}->(); } 
 
} while (1); 
 
sub get_input { 
    my $prompt = shift; 
    print $prompt; 
 
    chomp( my $value = <> ); 
    return $value; 
} 
 
sub read_doc { 
    my $file = shift; 
    my %user; 
    open my $fh, '<', $file or die $!; 
    while (<$fh>) { 
        my ( $name, $grp ) = ( split /:/ )[ 0, 4 ]; 
        $user{$name} = $grp; 
    } 
 
    return \%user; 
} 
 
sub admin_menu { 
    print << "UNIX_ADMIN"; 
 
Admin Menu 
 
To Add a User,     press 1: 
To Delete a User,  press 2: 
To Add a group,    press 3: 
To Delete a group, press 4: 
To Exit this Menu, press 5: 
 
UNIX_ADMIN 
 
}