G'day Sharath,

I'd recommend starting by cleaning up your code. I don't know if you've shown everything here: there's a few things that could potentially cause problems that can easily be avoided. Here's some suggestions:

• Use the strict and warnings pragmata. Initially, this will generate quite a few errors: most, if not all, of these can be fixed by simply declaring your variables with my.
• Avoid Indirect Object Syntax: see perlobj: Invoking Class Methods for a strongly worded explanation of why this syntax is discouraged.
• Use lexical filehandles: see open for a discussion of this.

Your current code:

my $req;

while ($req = ...
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would probably be better as:

while (my $req = ...
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And I suspect:

chomp;
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is supposed to be:

chomp $req;
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Once you've done that, it's possible your current problems may be resolved (I'm unfamiliar with this adb program you mention, so I don't really know). However, assuming that's not the case, look at eval for a way to trap errors: you'll want the block form of eval which you'd code something like this:

eval {
    # Code which might generate an error
}
if ($@) {
    # Handles any errors here
    # $@ holds the error message
}
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