in reply to A Perl aptitude test

I think that problem solving skills are more important than syntactical knowledge. A better question would be to ask them how they'd measure network traffic on a unix server. That way, you can drill down on specifics without getting hung up on syntax issues that would be found and corrected during the development process.

Example:

"If it's going to run as a one-shot, I'd run netstat using flags to isolate only the information I need and discarding the rest. I'd put a system call in a loop, use split to assign the different name-value pairs to a hash, and print them to STDOUT or to a file as CSV so we can import the data into an Excel spreadsheet or a graphing utility. If it's going to be running as a part of a standard test suite, I'd use a Unix::netstat instead of a system call to save CPU cycles. I could be wrong about the specific module name, but I'm sure that there's a module on CPAN to drive netstat. BTW, if you want to measure CPU and memory and disk i/o as well, sar is probably a better choice than netstat."

At this point, the examiner can determine that the interviewee knows something about unix and its internal monitoring tools, CPAN, hashes, the expense involved in doing repeated system calls, and how to present data. Plus, they have a bead on how to develop a quick-and-dirty tool vs. a productized tool suite. The specific syntax of netstat and split are things that can be checked once coding has begun. It's far more important to see the thought process and system experience than to nitpick over syntax. If you hire them, they'll have the Camel book on their desk anyway, so why freak out over comma placement?

-Logan
"What do I want? I'm an American. I want more."

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Re: Re: A Perl aptitude test
by Jenda (Abbot) on May 05, 2003 at 16:11 UTC

    netstat? Unix::netstat? sar? If this aint domain specific syntactic fluff than what is?

    I thought we are talking about a Perl test here, not a Unix admin one. If you asked me the only reply you could get is "I'd search CPAN and PerlMonks to find something I can use/tweak to our needs".

    Jenda
    Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.
       -- Rick Osborne

    Edit by castaway: Closed small tag in signature

[reply]
      Ah, but if you didn't know something about netstat or sar, you wouldn't be applying for a tool development job in a unix shop, would you? My point is that it's better to ask about the application of the skill than the syntactic details of the tool itself. If you were hiring a carpenter, you'd ask about how they would build different things, not the design of different types of hammers. Obviously, if you're applying for a postition in a Windows-based company or a development position where networking isn't an issue, the question would be different. The concept, however, remains valid.

      -Logan
      "What do I want? I'm an American. I want more."

[reply]

        Why not? It's (should be) the programming skills that matter, not the knowledge of the tools in a particular version of a particular OS. As long as there is someone who can tell me about sar I don't really need to know about it myself. Tool developer != admin.

        It takes no time to read the docs of such a tool, but it does take a lot of time to learn to design and write decent code.

        The interview should include concepts like flocking, pipes, non-blocking IO, semaphores/mutexes, sockets, ...

        If you were hiring a carpenter, you'd ask about how they would build different things, not the design of different types of hammers.

        I agree completely with this sentence, I just think you ARE asking about the design of a hammer.

        Jenda
        Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.
           -- Rick Osborne

        Edit by castaway: Closed small tag in signature

[reply]

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