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Full Discussion: A Perl Syntax Question.
Top Forums Shell Programming and Scripting A Perl Syntax Question. Post 302887941 by LinQ on Tuesday 11th of February 2014 08:20:45 PM
Old 02-11-2014
A Perl Syntax Question.

Greetings!

Here's what I believe is a "simple one" for the community tonight Smilie

What I'm trying to do is assign a "true/false" value to a variable depending upon whether a named process (some-process) exists; and then test for this value in the succeeding logic. I banged my head against the wall forever this afternoon trying to get it right:
Code:
$value = '$(pgrep some-process | wc) -gt 0';

if ($value)
{
  do something;
}

else
{
  do something else;
}
.
.
.

Can't quite get the syntax here. Anyone have a quick moment?

Thanks --

EDIT:
Looking @ pgrep a little closer, would something like this work just as well (or better):
Code:
'$(pgrep some-process > /dev/null)';

Smilie

Last edited by LinQ; 02-11-2014 at 10:30 PM.. Reason: Added material . . .
 

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Net::DNS::Question(3)					User Contributed Perl Documentation				     Net::DNS::Question(3)

NAME
Net::DNS::Question - DNS question class SYNOPSIS
"use Net::DNS::Question" DESCRIPTION
A "Net::DNS::Question" object represents a record in the question section of a DNS packet. METHODS
new $question = Net::DNS::Question->new("example.com", "MX", "IN"); Creates a question object from the domain, type, and class passed as arguments. qname, zname print "qname = ", $question->qname, " "; print "zname = ", $question->zname, " "; Returns the domain name. In dynamic update packets, this field is known as "zname" and refers to the zone name. qtype, ztype print "qtype = ", $question->qtype, " "; print "ztype = ", $question->ztype, " "; Returns the record type. In dymamic update packets, this field is known as "ztype" and refers to the zone type (must be SOA). qclass, zclass print "qclass = ", $question->qclass, " "; print "zclass = ", $question->zclass, " "; Returns the record class. In dynamic update packets, this field is known as "zclass" and refers to the zone's class. print $question->print; Prints the question record on the standard output. string print $qr->string, " "; Returns a string representation of the question record. data $qdata = $question->data($packet, $offset); Returns the question record in binary format suitable for inclusion in a DNS packet. Arguments are a "Net::DNS::Packet" object and the offset within that packet's data where the "Net::DNS::Question" record is to be stored. This information is necessary for using compressed domain names. COPYRIGHT
Copyright (c) 1997-2002 Michael Fuhr. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. SEE ALSO
perl(1), Net::DNS, Net::DNS::Resolver, Net::DNS::Packet, Net::DNS::Update, Net::DNS::Header, Net::DNS::RR, RFC 1035 Section 4.1.2 perl v5.8.0 2002-10-12 Net::DNS::Question(3)
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