Re: underscores and function names

["Michael R. Hines" <mhines@xxxxxxxxxx>]

That's true.

I often do similar bypasses with many of the __skb socket buffer functions.

- Michael

At 01:46 PM 1/3/2005, Om wrote:
> Michael R. Hines wrote:
> > The ones with underscores usually have matching functions withOUT 
> > underscores. They are meant to be private calls.
> > The ones without underscores usually call the one with underscores, and 
> > these are the ones that actually do the work.
> > The kernel will sometimes call the underscore'd functions directly 
> > because it knows what it's doing.......
> > But while programming, we should generally call the ones without them.
> Yes, unless we know what we do ;-)
> for example, lets take arch/i386/lib/usercopy.c : copy_to_user(). This 
> function performs some checks (access_ok()) on the passed parameter and 
> then call the actual function that implements the functionlity 
> include/asm/uaccess.h:__copy_to_user(). The implementation might use other 
> functions as well.
>
> If the target area is already checked for access_ok, then the caller call 
> skip the call copy_to_user() and make a call directly to __copy_to_user(). 
> This will save some time/code size.
>
> I am not familiar with functions with single underscore starting. But the 
> idea is same.
>
> HTH.
> Om.
>
> --
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/*********************************/
Michael R. Hines
Grad Student, Florida State
Dept. Computer Science
http://www.cs.fsu.edu/~mhines/
Jusqu'à ce que le futur vienne...
/*********************************/


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