Logging into multiple devices

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

I'm using Net::Telnet::Cisco, How do I keep the script from dying if the login fails. I'm testing a list of login attributes for many devices and I know some will logins will fail, but I want the script tell me and continue, not die. Something like-

 $t->login(Name     => $login_att[11],
                  Password =>$login_att[12]) || warn "Can't Login: " .
+ $t->errmsg;
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Comment on Logging into multiple devices Download Code

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Re: Logging into multiple devices by Arunbear (Prior) on Oct 26, 2004 at 14:44 UTC
Assuming that the `login` method is raising the exception: `eval { $t->login( Name => $login_att[11], Password => $login_att[12]) }; warn "Can't Login: $@" if $@;` [download]	[reply] [d/l] [select]
Re: Logging into multiple devices by gaal (Parson) on Oct 26, 2004 at 14:49 UTC
I'm not familiar with this module, but in general you can catch calls to `die` by wrapping the fatal code with `eval`. Your code will look something like this: `eval { $t->login(Name => $login_att[11], Password =>$login_att[12]); 1 } or warn "Can't Login: " . $t->errmsg;` In the general case, `$@` has the error you would normally get printed on stderr when the script died.	[reply] [d/l] [select]
Re: Logging into multiple devices by wilbur (Novice) on Oct 26, 2004 at 15:03 UTC
Thank you for the replies, "eval" will come in handy. I should have known that. I just found another answer, `$t->errmode("return");` also does the trick.	[reply] [d/l]
Re^2: Logging into multiple devices by gaal (Parson) on Oct 26, 2004 at 18:24 UTC
What works best is up to you to decide, of course, since you know your how the rest of your code is organized. `die` and `eval` present a different conceptual model from having functions place error codes in return values; in my experience, they can seriously simplify code -- for instance where the code has long failure-prone flows.	[reply] [d/l] [select]