-bash-4.1$ ./test1.pl 
# open_ex: ['ssh','-O','check','-T','-S','/home/kburns/.libnet-openssh-perl/kburns-10.10.10.-20023-380016','-l','kburns','10.10.10.1','--']
# _waitpid(20025) => pid: 20025, rc: 
# open_ex: ['ssh','-S','/home/kburns/.libnet-openssh-perl/kburns-10.10.10.-20023-380016','-l','kburns','10.10.10.1','--','!bash']

##</code><code>##

my $ssh = Net::OpenSSH->new($host, user => $USERNAME, password => $PASSWORD, str
ict_mode => 0);

$ssh->error and die "Couldn't establish SSH connection: " . $ssh->error;

$ssh->system('!bash') or die "remote command failed: " . $ssh->error;

print "!bash done\n";

$ssh->system('pwd') or die "remote command failed: " . $ssh->error;

print "pwd done\n"; # never gets here. it hangs