Re: (patch) Improved documentation and examples of dynamic modules

["Kamil Rytarowski" <n54%gmx.com@localhost>]

Paul Goyette wrote:
> OK, I looked at all of the examples, except for the lua one (I am 
> lua-clueless).  Everything looks OK to me, and I don't see any reason 
> not to commit these.
> 

Please try to follow the code, it should illuminate you. If it's too
difficult it should be corrected.

> I do, however, have a request...
> 
> The "happy" module makes a claim that "4 digit numbers cannot cycle", 
> and uses a cache[] table for all numbers below 1000.  Can you please 
> provide a reference to back up the "cannot cycle" claim?  :)  And please 
> initialize (or reinitialize) the entire cache[] array in your modcmd's 
> INIT routine, rather than a single static initialization.  (It could 
> make a difference if the module were ever "built-in" to a kernel ...)
> 

There are two algorithms: naive and optimal. The naive one uses caching
and the optimal check whether we are in the cycle: 4, 16, 37, 58, 89,
145, 42, 20. The claims comes from this statement that the largest number
from the cycle is 3-digit.

I can go for the the optimal one and cut the caching design in the code.
In the module example the algorithm implementation shouldn't divert 
attention from the important part - how to implement read(2).

> Also, for all tests that create a cdevsw, please insert a comment to 
> ensure that the reader should verify that the number should be changed 
> if needed to avoid conflict with "real" devices.

I will do it.

> And maybe also note this in the README file?

Good idea.

> Definitely include a comment that these 
> modules should not be used on a "production" machine, just in case...
> 

I will put a line about it in the README file.

> Finally, I would appreciate it if other folks would weigh in on the 
> question of the directory hierarchy into which these examples should be 
> placed...
> 

I like it. Maybe place them in `share/examples/kmodules'?