in reply to Re: Empty string checking in output
in thread Empty string checking in output

tulic , i tried that but the else block is not executing. i can explain the behavior of the cisco device if a particular command is not present... if i telnet into cisco device it will show as 

2960#

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here at this prompt i want to check one command i.e 
2960#sh run | in ntp

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if the configuration is not present then it will show as same 
2960#

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so at this time the in array @output doesn't contain anything but i dont know why the else block is not executing

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Re^3: Empty string checking in output
by AnomalousMonk (Archbishop) on Aug 17, 2011 at 06:32 UTC
    ... the in array @output doesn't contain anything but ... the else block is not executing ...

    ... because, contrary to what you think, the  @output array contains something. Try printing/dumping the contents of the array. Also, what code are you actually running? 

    >perl -wMstrict -le
"my @output = ();
 ;;
 if (@output) {
   print qq{true clause: array not empty};
   }
 else {
   print qq{false clause: array empty};
   }
"
false clause: array empty

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      yes,i executed the block of code above its printing "true clause: array not empty" but how to find exactly what is there in that?i wrote dis code to check a configuration in cisco devices.

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        One way (there are many 'data dumpers'). Note: you must pass a reference to the array to the Dumper function. 

        >perl -wMstrict -le
"use Data::Dumper;
 my @output = qw(1 2 foo);
 print Dumper \@output;
"
$VAR1 = [
          '1',
          '2',
          'foo'
        ];

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        See Data::Dumper.

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