Something wrong ... 
~/script/perl/temp@myserver >cat !$
cat ./perl.tty4
#!/usr/bin/perl -w

use strict;

my %ttys_of;

foreach (`who`) {
        my ($user, $tty) = /(\S+)\s+(\S+)/;
        push @{$ttys_of{$user}}, $tty;
}

foreach my $user (sort keys %ttys_of) {
        my $ttys = @{$ttys_of{$user}};
        
        if (@$ttys == 1) {
                print "user $user is ONLY logged in at one place $ttys
+->[0]\n";
        } else {
                print "user $user is logged in at: " . join(' ', sort 
+@$ttys) . "\n";
        }
}
~/script/perl/temp@myserver >./!$
././perl.tty4
Can't use string ("1") as an ARRAY ref while "strict refs" in use at .
+/./perl.tty4 line 15.

main::(././perl.tty4:13):             my $ttys = @{$ttys_of{$user}};
  DB<1> 
main::(././perl.tty4:13):             my $ttys = @{$ttys_of{$user}};
  DB<1> 
main::(././perl.tty4:15):             if (@$ttys == 1) {
  DB<1> 
Can't use string ("1") as an ARRAY ref while "strict refs" in use at .
+/./perl.tty4 line 15, <IN> chunk 142.
Debugged program terminated.  Use q to quit or R to restart,
  use O inhibit_exit to avoid stopping after program termination,
  h q, h R or h O to get additional info.

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In reply to Re^2: reference question by convenientstore
in thread reference question by convenientstore

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