Beefy Boxes and Bandwidth Generously Provided by pair Networks
Do you know where your variables are?
 
PerlMonks  

Re: Net::Snmp Attempt

by Abigail (Deacon)
on Jul 12, 2001 at 01:30 UTC ( #95861=note: print w/ replies, xml ) Need Help??


in reply to Net::Snmp Attempt

I would write is as follows:

#!/usr/bin/perl -w use strict; use Net::SNMP; Usage () unless @ARGV == 2; my ($session, $error) = Net::SNMP -> session ( -hostname => $ARGV [0], -community => $ARGV [1], ); $session or die "Session error: $error"; my $tableid = "1.3.6.1.4.1.1991.1.1.4.6.1.1"; my $table = $session -> get_table ($tableid) or die "request error: ", $session -> error; foreach my $oid (keys %$table) { if ($oid =~ /^\Q$tableid\E\.(\d+)/) { print "Real server ", $table -> {$oid}, ", port ", $table -> {"$tableid.5. +$1"}, ", is bound to virtual server ", $table -> {"$tableid.2. +$1"}, ", on port ", $table -> {"$tableid.3. +$1"}, "\n"; } } my $sysid = "1.3.6.1.2.1.1.4.0"; my $syscontact = $session -> get_request ($sysid) or die "Request error: ", $session -> error; print "For help or questions contact: ", $syscontact -> {$sysid}, "\n" +; $session -> close;
Some differences: no global variables (with use vars). No magical constants that are repeated. Taken care of the special meaning of a dot inside a regex. Anchored the regex. Used parenthesis to capture relevant field. No needless concatenation in print or die. Success is checked right away and not in a separate statement. Just one check to see if there are enough arguments.

-- Abigail


Comment on Re: Net::Snmp Attempt
Select or Download Code
Re: Re: Net::Snmp Attempt
by Jer (Initiate) on Jul 13, 2001 at 01:55 UTC
    Abigail,

    Thanks for your help. I understand most of the changes you made. I especially appreciate the regex cleanup. I'm puzzled by the lines

    $table -> {"$tableid.5.$1"}, $table -> {"$tableid.2.$1"},

    What does the $1 do?

    Jer

      $1 doesn't really "do" anything; it's a variable having a value. It is set by the preceeding regular expression which contains a set of parenthesis. The part of the string that is matched by the sub expression in the parens is put in $1. This avoids needing to do the split and getting the last element. See also the perlre manual page.

      -- Abigail

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://95861]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others scrutinizing the Monastery: (14)
As of 2014-07-30 19:03 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    My favorite superfluous repetitious redundant duplicative phrase is:









    Results (239 votes), past polls