de-CCS-in-7-lines-perl

What? Posting source code is illegal? There goes the monestary! (Quick get me the Perl2English translator) :)

Anyway, I did the minor deobfuscation, and I'm confused over the use of "read+", "unpack+" and "pack+". Sounds like it's something that could save some bytes in rsa-in-3-lines-perl.

--
$Stalag99{"URL"}="http://stalag99.keenspace.com";

Comment on de-CCS-in-7-lines-perl Download Code

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(tye)Re: de-CCS-in-7-lines-perl by tye (Sage) on Mar 08, 2001 at 01:09 UTC
The "read+" can be replaced with "read ". However, if you replace "pack+" with "pack " and then end up with "pack (expr),arg,arg" then it gets parsed as "(pack(expr)),arg,arg" while "pack+(expr),arg,arg" gets parsed as "pack((expr),arg,arg)". My quick look didn't tell me if that was actually a problem for this particular script or not. The "unary plus" trick is a faily common way of making a call to a predeclared function without using parens around the arguments when the first arugment might have parens around it. - tye (but my enemies call my lawyers)	[reply]

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(tye)Re: de-CCS-in-7-lines-perl
by tye (Sage) on Mar 08, 2001 at 01:09 UTC

The "read+" can be replaced with "read ". However, if you replace "pack+" with "pack " and then end up with "pack (expr),arg,arg" then it gets parsed as "(pack(expr)),arg,arg" while "pack+(expr),arg,arg" gets parsed as "pack((expr),arg,arg)". My quick look didn't tell me if that was actually a problem for this particular script or not.

The "unary plus" trick is a faily common way of making a call to a predeclared function without using parens around the arguments when the first arugment might have parens around it.

tye

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