Messages in this thread |  | | | Date | Fri, 25 May 2007 14:14:21 -0700 (PDT) | | Subject | Re: double exclamation (!!) suckage in the kernel | | From | David Miller <> |
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From: "Satyam Sharma" <satyam.sharma@gmail.com> Date: Sat, 26 May 2007 01:53:59 +0530
WHat is with multiple people asking about "!!" all of a sudden today?
> Are all these occurrences merely the debris of > s/something/!notsomething/g kind of patches or is there some > dark, unknown C / gcc wizardry I have absolutely no clue of?
"!!" is used in contexts where pointers might be being tested as well as plain integers, the "!!" turns a pointer into the equivalent integer boolean for testing.
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