What you get is a warning about an undefined $_.

If you look closely you see that it complains about the errormode-sub.

This is triggered because you fail to remove the newlines from the ips you read from the file (after <IPS> $_ contains not "1.2.3.4" but "1.2.3.4\n" - get rid of that with a chomp), so the ip you pass to Net::Telnet is not valid and so the errormode-sub is triggered.

In this sub $_ is no longer the value you read from the file, probably because Net::Telnet localized $_.

If you would use a lexical variable (rather than $_), e.g. 

while (my $ip = <IPS>) {
 chomp $ip;
 ...

[download]

You could then refer to this $ip variable in your errmode-sub (which would then be a closure).

In reply to Re: Telnet list of IP and get information stored to a file by morgon
in thread Telnet list of IP and get information stored to a file by sanju7

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