Re: how to handle login failures with Net:::SSH::Perl?

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Re^2: how to handle login failures with Net:::SSH::Perl? by jfroebe (Parson) on Sep 21, 2004 at 13:25 UTC
Unfortunately, no. Ends up being we need to place the $ssh->cmd() within an eval block. Net::SSH::Perl was designed to die() if the connection attempt fails. I was hoping to avoid an eval block as I really don't like them because they require a recompilation each time we encounter an eval block. As the camel book says, it is a performance hit. `eval { ($stdout, $stderr, $exit) = $ssh->cmd("df -k $dump_dir"); }; if ($@) { print "SSH Connection attempt failed\n" if ($@ =~ m/Permission denied/i); }` [download] The login() method doesn't do anything but set the settings for the connection.. It doesn't actually connect to anything. Jason L. Froebe No one has seen what you have seen, and until that happens, we're all going to think that you're nuts. - Jack O'Neil, Stargate SG-1	[reply] [d/l]
Re^3: how to handle login failures with Net:::SSH::Perl? by runrig (Abbot) on Sep 21, 2004 at 16:40 UTC
...they require a recompilation each time we encounter an eval block...it is a performance hit. There is no "performance hit" from the eval in your code (at least not nearly as much as you think there is). `eval $string` has a performance hit, as perl does have to compile the code in `$string` each time, but not in `eval { BLOCK }`, because the code in the BLOCK is already compiled. See the eval docs in perlfunc.	[reply] [d/l] [select]
Re^4: how to handle login failures with Net:::SSH::Perl? by jfroebe (Parson) on Sep 21, 2004 at 18:30 UTC
insert a Home Simpson DOH! ;-) Jason L. Froebe No one has seen what you have seen, and until that happens, we're all going to think that you're nuts. - Jack O'Neil, Stargate SG-1	[reply]
Re^3: how to handle login failures with Net:::SSH::Perl? by elwarren (Priest) on Sep 21, 2004 at 15:45 UTC
I think you're going to see an even more significant performance hit from running ssh and df -k over and over before you notice a performance penalty from eval :-)	[reply]