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Re: __words__

On Tue, Jan 07, 2003 at 02:05:47PM +0530, SACHIN PRASAD wrote:
> hi all ,
> In the kernel code , i see lot of __words__ what are they ?
> do they hold some special meaning or some programming convention
> also some are having one underscore some have two ...
> regards
> sachin

Usualy, they are ANSI protected keywords. That is, C extensions that
should not generate warnings on ANSI-only compiler. You can find them in
user-land programs too. Just the kernel uses them a LOT.

GCC understands both __foo__ and foo variants of all it's extension
keywords and both variants can usualy be seen in kernel.

On the other hand __identifiers are a convention to distinguish
functions, that can only be used in special circumstances (many "foo"
funtions call __foo after doing some checking, locking locks etc.).

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						 Jan 'Bulb' Hudec <bulb@ucw.cz>
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