Net::telnet difficulty

mosh has asked for the wisdom of the Perl Monks concerning the following question:

Hi All,
Pls. need your help. I'm using Net::telnet module on perl inorder to make a telnet connection to device:

...
$telnet= new Net::Telnet(Host=>1.1.1.11,Port=>9000,Timeout=>10);
...
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Now, if the Net::telnet succeeded, it's great, but if it failed the script dies after timeout of 10 seconds, and I would like the perl script to go on after this T.O.

Anyone have an idea how to do it, while displaying an error message ilke FAIL to the screen ?
Thanks a lot,
Mush. _{janitored by ybiC: Balanced <code> tags, minor formatting tweaks for legibility}

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Re: Net::telnet difficulty by hossman (Prior) on Aug 10, 2004 at 08:05 UTC
Please read the docs for a module before posting a question about it. I've never used Net::Telnet, but I spent less then 45 seconds skimming the docs before I found the answer to your question. I'll give you a hint, grep for (and look at) all occurences of "Errmode" or "errmode".	[reply]
Re^2: Net::telnet difficulty by mosh (Scribe) on Aug 10, 2004 at 10:16 UTC
I've read the docs but if you meant to use Errmode=>"return" it is not working, since the telnet doesn't die in case of T.O. What I want is that the telnet dies after T.O. but the perl script will continue and won't die too. Mosh.	[reply]
Re^3: Net::telnet difficulty by amt (Monk) on Aug 10, 2004 at 14:45 UTC
I am assuming that you want your code to perform a different action, and take a different path if the Net::Telnet object doesn't exist. One option is put your non-connected code into a function and then have that execute. For example: `my $t = new Net::Telnet(..) \|\| branch(args); #code to occur if the telnet session is established. exit; sub branch { #code here and bail out exit; }` [download] amt	[reply] [d/l]
Re^3: Net::telnet difficulty by hossman (Prior) on Aug 11, 2004 at 07:00 UTC
I never said to use Errmode=>"return" .. I said to read the docs and pay attention to every mention of Errmode. If you want to use Errmode=>"return" that's fine, but there are several other options. Since you didn't post any runnable code, no one can even begin to help you figure out why it's not working the way you want, we can only guess. Me, I spent about 2 minutes writting this, which seems to me to work just fine, so I have no idea what your problem is.... #!/usr/local/bin/perl -l use strict; use warnings; use Net::Telnet; sub t { return scalar(localtime) . " - "; } print t(), "Starting"; my $tel = new Net::Telnet(); $tel->open(Host=>'www.yahoo.com', Port=>9000, Timeout=>10, Errmode=>'return') or print t(), "Couldn't Open: ", $tel->errms +g(); print t(), "Timed Out: ", $tel->errmsg() if $tel->timed_out(); print t(), "still going strong"; __END__ laptop:~> monk.pl Tue Aug 10 23:56:32 2004 - Starting Tue Aug 10 23:56:43 2004 - Couldn't Open: problem connecting to "www.y +ahoo.com", port 9000: connect timed-out Tue Aug 10 23:56:43 2004 - Timed Out: problem connecting to "www.yahoo +.com", port 9000: connect timed-out Tue Aug 10 23:56:43 2004 - still going strong laptop:~> [download]	[reply] [d/l]
Re: Net::telnet difficulty by toma (Vicar) on Aug 10, 2004 at 16:09 UTC
You can probably follow the advice above and get timeouts to do what you need. If not, try the Expect module. There are more Expect examples here. You may find that Expect does a lot of other things that your program needs for dealing with a telnet session. It should work perfectly the first time! - toma	[reply]