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BooK (2612)

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Obfuscation []. Pink []. HTTP::Proxy []. YEF []. Fishnet []. Kapow []. Cog's [] bitch []. Invitation []. White [] Camel []. Nuff' said.

Journal of BooK (2612)

Tuesday January 15, 2002
12:47 PM

Obfuscation and core hacking 101

[ #2147 ]

Well, this new obfu has been long overdue (since YAPC::Europe 2001 auction), and I just started some real coding today (oh my gawd, I reinstalled Perl at work, which means I'll probably be less efficient (my job doesn't require any Perl skills)).

This yet another script to print a witty(?) message. (Sorry Dave, I really wanted to output an image, but I also wanted to give you this script. So I'll code this one for you, and if I ever get 'round to output an image, this other one will be also for you too (although later).)

While reading Effective Perl Programming (aka "The Shiny Ball Book"), I learnt a trick about substr which I immediately wanted to try. After trying it a little more than reasonable, the scripts I wrote with this trick stopped "working". They didn't DWIM anymore. I suspect it's some kind of a "bug" (actually it's more like a feature that doesn't work but is never used, except by people like me. Yuck.) in substr.

I began to look at the source. But I am not a Perl core hacker, so I could only track the problem to a few macro-filled lines. Now I should read perlhack, write a full test case to prove my point, check if it still doesn't work with bleadperl, and either ask for help on p5p (without a patch?) or try to fix this myself. Since this non-working feature is never used, I guess I have all the time I want... :-)

Had this "feature" worked, I suppose I'd have just used this trick for Dave's obfu. Which I do, but it's more difficult to do without, and takes longer... I am glad I am not doing this on my spare time! ;-)

(And no, don't ask, I won't tell you... It's mine!)

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  • Well, je dois dire que cette mystérieuse feature excite ma curiosité.

    If you want to get to core hacking, read also perlguts, use perlapi for reference, and find Simon's tutorials -- I haven't any URL handy but Google should be able to help, as usual.

    Also, if you've found a bug, use perlbug. Or do you want to keep it sekret ? ;-)

  • Not secret, but it's so insignificant, I would not really call this a bug... Maybe an "unsuspected misbehavior".

    Anyway, je vois que tu es français (or live in France, at least): I suppose you are not the only Perl hacker in Lyon. Never thought about creating We have already found [] the perfect place [] for the meeting!

    • Yeah, I know this Café.

      About creating neat idea, but I don't know much Perl hackers here.

      • I suppose creating the group will attract other Lyon Perl hackers. Get in touch with the other French Perl Mongueurs [] (mostly [] people) at mongueurs[at]

        There's already Toulouse [] and Marseille [], why not Lyon?

        Et pourquoi on continuerait pas en français par mail ? mongueurs(à) :-)