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POUsing a variable from a file in a loop
 

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  1. POUsing a variable from a file in a loop
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    <p>I bumped my head on this piece of code for two days without any success: What I need to do is obtain a list of IP addresses starting from a long list of NETWORKS in this format: </p> <p>NETWORK NUMBER_OF_HOSTS<BR> 192.168.1.0 512</p> <p>I've found this bunch of code in the Net:IP module that seems perfect for my needs:</p> <pre><code>my $ip = new Net::IP ('192.168.1.0 + 512'); do { print $ip-&gt;ip(), "\n"; } while (++$ip); </code></pre> <p>With the NETWORK and HOST value declared explicitly the snippet works flawlessly, when I use it inside a while loop passing the data through variables, the problems start. After many tries I've modified the list as follows:<BR></p> <p>'192.168.150.0 + 512'</p> <p>And this is the resulting script:</p> <pre><code>#!/usr/bin/perl use strict; use warnings; use Net::IP; open(MYFILE, "ips.txt") or die "$0: Can't open input file $input: $!\n"; while (&lt;MYFILE&gt;){ chomp $_; my $ip = new Net::IP ($_); do { print $ip-&gt;ip(), "\n"; } while (++$ip); } close(MYFILE); </code></pre> <p>When I try to execute it gives me the following error:</p> <blockquote> <p>Can't call method "ip" on an undefined value at ./iplist.pl line 14, line 1.</p> </blockquote> <p>If I print the variable inside the while loop with this <code>print $_,"\n";</code> it prints the variable correctly, so where am I wrong? Any help is appreciated.</p> <p>UPDATE1: od output for ips.txt</p> <pre><code>0000000 ' 4 1 . 5 7 . 1 1 6 . 0 + 1 0000020 0 2 4 ' \n ' 4 1 . 5 7 . 1 9 2 . 0000040 0 + 1 6 3 8 4 ' \n ' 4 1 . 6 0000060 6 . 1 9 2 . 0 + 1 6 3 8 4 ' 0000100 \n ' 4 1 . 7 4 . 8 0 . 0 + 4 0000120 0 9 6 ' \n ' 4 1 . 7 5 . 4 8 . 0 0000140 + 4 0 9 6 ' \n ' 4 1 . 7 6 . 0000160 2 4 . 0 + 2 0 4 8 ' \n ' 4 1 0000200 . 7 7 . 6 4 . 0 + 2 0 4 8 ' 0000220 \n ' 4 1 . 7 8 . 4 0 . 0 + 1 0000240 0 2 4 ' \n </code></pre>
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    1. USDiego
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    1. CONits aside, the program is fine. The error must be in the input file. What's the output of `od -c ips.txt`?
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      1. USikegami
    2. CO@ikegami I've added the first lines of the od output
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      1. USDiego
 

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