Dear Monkers,

I am playing with grep and split but I am getting some errors and I don't understand where is the problem.

Using Expect module I am getting output from a device, and then I try to organize the output nicely with this:

sub _parse_output {
    my $self    = shift;
    my @output  = @_;
    my @return  = undef;

    foreach(@output) {
        next if (!defined)
        my @tmp = split /\r\n/;
        push @return, @tmp;
    }

    return \@return;
}

[download]

The main idea is to put each line into each slot of the array, then on the other hand sometimes I need to grep some data but when I use grep I get an error:

Use of uninitialized value $_ in pattern match (m//) at ./random_ssh.pl line 133.

This is line 133:

$active_sessions = grep (/Session No:/, @$output);

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Where @$output contains the value returned by the _parse_output routine. Do you know what's happening?

Variable $output contains the following (I used Data::dumper): 

$VAR1 = [
          undef,
          'show system user current ',
          '',
          'Name: root;  Login Time: 03/27/2009 17:13:48;  Session No: 
+4367',
          'Name: root;  Login Time: 03/27/2009 17:30:55;  Session No: 
+4374',
          'Name: root;  Login Time: 03/27/2009 17:31:16;  Session No: 
+4376',
          'Name: root;  Login Time: 03/27/2009 17:31:38;  Session No: 
+4379',
          'Name: root;  Login Time: 03/27/2009 17:31:47;  Session No: 
+4380',
          'Name: root;  Login Time: 03/27/2009 17:31:57;  Session No: 
+4381',
          'Name: root;  Login Time: 03/27/2009 17:32:17;  Session No: 
+4382',
          'Name: root;  Login Time: 03/27/2009 17:32:27;  Session No: 
+4383',
          'Name: root;  Login Time: 03/27/2009 17:32:46;  Session No: 
+4385',
          'Name: root;  Login Time: 03/27/2009 17:34:01;  Session No: 
+4389',
          'Name: root;  Login Time: 03/27/2009 18:12:08;  Session No: 
+4397',
          'Name: root;  Login Time: 03/27/2009 21:45:32;  Session No: 
+4415',
          'Name: root;  Login Time: 03/27/2009 22:15:05;  Session No: 
+4423*',
          'Name: root;  Login Time: 03/27/2009 22:15:17;  Session No: 
+4424',
          ' '
        ];

[download]

Any ideas are appreciated, thanks!

gmoque

In reply to grep throws an exeption by gmoque

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