perl - Can not send data to IO::Socket::INET in conditional statement -

i have issue communicating external system via io::socket::inet. try login , send multiple commands system unfortunately does'n work if command print in line 58 under conditional statement. conditional statements in case required handle response data.

package net::cli::cisco;  use 5.006; use strict; use warnings fatal => qw(all);  use io::socket::inet; use carp;  use data::dumper; $| = 1;  sub new {     $class = shift;     %args  = @_;     $self  = bless {         _host     => $args{host}     || carp('no hostname defined'),         _username => $args{username} || carp('no username defined'),         _password => $args{password} || carp('no password defined'),         _logged_in => 0,     }, $class;     return $self; }  sub connect {     $self = shift;     $host = $self->{_host};     $port = 23;      $handle = io::socket::inet->new(         proto    => "tcp",         peeraddr => $host,         peerport => $port,         type     => sock_stream,         timeout  => 3     ) or die "can't connect port $port on $host: $!";      $shc = "\r\n";     $self->{shc}    = $shc;     $self->{handle} = $handle; }  sub getinterface {     ($self) = @_;     $self->connect;     @cmd_list = ( "sh clock", "sh ip int brief" );     $self->send_cmd(@cmd_list); }  sub send_cmd {     ( $self, @cmd_list ) = @_;     $handle = $self->{handle};     $response;     while ( $response = <$handle> ) {          if ( $response =~ m/^username:/ ) {             print "conditional statements exec done!\n";             print $handle $self->{_username} . $self->{shc};         }          #print $handle $self->{_username} . $self->{shc};         print $response;         print $handle $self->{_password} . $self->{shc};         print $handle "enable" . $self->{shc};         print $handle $self->{_password} . $self->{shc};         print $handle "term leng 0" . $self->{shc};          foreach $cmd (@cmd_list) {             print $handle "$cmd" . $self->{shc};         }         print $handle "exit" . $self->{shc};      }      close($handle); }  1;  $x = __package__->new(     "host"     => "1.1.1.1",     "username" => "user",     "password" => "pw" ); $x->getinterface; 

well, can't see why code wrong. note: if recommend line 61 working fine. ideas?

after comment ikegami please find working subroutine below:

sub send_cmd { ( $self, @cmd_list ) = @_; $handle = $self->{handle}; $response; start: while ( $response = <$handle> ) {         print $response;         if ( $response =~ m/[^username:|^password:|\$%#:>]/ ) {             print $handle $self->{_username} . $self->{shc};             print $handle $self->{_password} . $self->{shc};             print $handle "enable" . $self->{shc};             print $handle $self->{_password} . $self->{shc};             print $handle "term leng 0" . $self->{shc};             foreach $cmd (@cmd_list) {               print $handle "$cmd" . $self->{shc};             }              print $handle "exit" . $self->{shc};         } else {             goto start;         }     } close($handle);