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Re^6: uninitialized values

by gaurav (Acolyte)
on Aug 20, 2013 at 09:18 UTC ( #1050164=note: print w/replies, xml ) Need Help??

in reply to Re^5: uninitialized values
in thread uninitialized values

Ok R. Below,I am trying to modify and add comment in my code

#!/usr/bin/perl -w use String::Util 'trim'; =head1 NAME - This script works on Linux system pings a host and re +turns statistics data. =head1 VERSION Version 1.0 =head1 AUTHOR Gaurav Dubey ( =head1 SYNOPSIS ./ [-c --> count (Number of echo requests to be sent)] +[-i --> interval (Interval in milliseconds between echo requests)] [ +-s --> packetsize (Size of icmp packet)] [-h --> destinationIP (Ip ad +dress of destination host)] [-w --> AllowableTime (Max time in second +s for sending receiving echo requests/reponse)]" =head1 DESCRIPTION This pings a host via the system ping command and returns RTA ,Tx pack +ets,Rx packets,TTL,Packet-loss =cut use strict; use Getopt::Long; use Pod::Usage; my ($host,$count,$interval,$packetsize,$allowableTime); GetOptions( "h|host=s", \$host, "c|count=i", \$count, "i|interval=i", \$interval, "s|packetsize=i", \$packetsize, "w|allowableTime=i",\$allowableTime, ); #pod2usage("$0: No host given!\n") unless($host); pod2usage("$0:No host given!\n") unless($host && $host =~ /^((([2][5][ +0-5]|([2][0-4]|[1][0-9]|[0-9])?[0-9])\.){3})([2][5][0-5]|([2][0-4]|[1 +][0-9]|[0-9])?[0-9])$/); $count = 5 unless ($count); $interval = 1 unless ($interval); $packetsize = 56 unless ($packetsize); $allowableTime = 1 unless ($allowableTime); #Here I am opening a ping process on linux system . open CMD, "/bin/ping -c $count -i $interval -s $packetsize -w $allowab +leTime $host |" or die "Can't open ping: $!"; #This code has been working fine by executing "./ -h 192. +168.1.150 -c 1" from terminal.And I want to mention it that this host + is up and running with in our network. my (@values1,@val1,@values2,@val2,@values3,@values4,@values5); while (<CMD>) { #In below, if-block I am extracting the host-ip,Packet Size,Packet+Hea +der Size from the output line #PING ( 56(84) bytes of data if ( $_ =~ /PING/ ){ @values1 = split ; @val1 = split(/\(/,$values1[3]); $val1[1] =~ s/\)//; } #Below if-block has been used to extract the TTL values from the line +"64 bytes from icmp_req=1 ttl=254 time=4.43 ms" #which is 254 if ($. == 2) { @values2 = split; @val2 = split(/\=/ , $values2[5]); } #in this if-block I am extracting the transfer-recieved packets and pa +cket loss ,from the output line "3 packets transmitted, 3 received, 0 +% packet loss, time 2003ms" if ($_ =~ /packets/) { #print "$_ "; @values3 = split; } #In last if-block I am extracting the rtt avg/max/min/med values ,from + the output-line "rtt min/avg/max/mdev = 2.113/2.895/4.434/1.089 ms" if ($_ =~ /^rtt/) { #print "$_ "; @values4 = split /\=/; @values5 = split(/\// ,$values4[1]); } } #print "$values1[1] \n"; # print "$val1[0] \n"; #print "$val1[1] \n"; #print "$val2[1] \n"; #print "$values3[0] \n"; #print "$values3[3] \n"; #print "$values3[5] \n"; #print "$values4[1]"; #my $min = trim($values5[0]); #print "$min\n"; #print "$values5[1] \n"; #print "$values5[2] \n"; #print "$values5[3] "; close CMD

So its working fine

Now when I passed an IP which is not present in our company network say

ping -c 1 PING ( 56(84) bytes of data. --- ping statistics --- 1 packets transmitted, 0 received, 100% packet loss, time 0ms

So How can I relay a message by using perl that host is not present in our network?

But if it's present in our company's network but system is down.Say,

#ping -c 1 PING ( 56(84) bytes of data. From icmp_seq=1 Destination Host Unreachable --- ping statistics --- 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0 +ms

for this I have to say system is down.Remember here one thing that I am using this perl script on Fedora-14 Redhat Linux System

Replies are listed 'Best First'.
Re^7: uninitialized values
by Random_Walk (Prior) on Aug 20, 2013 at 09:44 UTC

    You really need to use some helpful names for your variables. I started to work on your code and gave up because while I have a good idea what this means:

    print "$hostname\n"; print "$ip\n"; print "$pkt_size\n"; print "$ttl\n";

    it will take me some time to work out what this means:

    #print "$values1[1] \n"; # print "$val1[0] \n"; #print "$val1[1] \n"; #print "$val2[1] \n";

    I would suggest, other than using sane variable names, that you alter your series of if statements to use the if/elsif/else construct. This will give you a way to catch the error conditions from your ping.

    On a more minor point, it looks like you only allow a restricted range of IP addresses for your $host value. Yet later you capture the IP used by ping. Is there a case where you ask it to ping n.n.n.n and it pings m.m.m.m? If not you can just use the IP you fed into it.


    Pereant, qui ante nos nostra dixerunt!

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