use strict;
use warnings;

my %users = %{user_paths()};
foreach my $user (keys %users) {
    if (-e "$users{$user}/MY_FILE") {
        open (FH2, "<$users{$user}/MY_FILE") or die "could not open $users{$user}/MY_FILE $!";
        while (my $line = <FH2>) {
            if ($line =~ /BASE_PORT=(\d+)/) {
                print  "$user --> $1";
            }
        }
    }
}

sub user_paths {
    my %users;
    open (FH1, "</etc/passwd") || die "Can't Open : $!";
        while (<FH1>) {
            my @user = split (/:/);
            if ( $user[2] > 500 ) {
                $users{$user[0]} = "$user[5]";
            }
        }
    return \%users;
}