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Re: New tools proposal: ioctlname and ioctldecode



On 02.04.2020 04:06, Mouse wrote:
>> We should maintain a contract that all new ioctl operations are
>> system wide unique.
>
> That is, unfortunately, unenforceable in the presence of a user base
> that writes and shares code.  If I #define IOCNEWTHING _IO('?',7) and
> someone else #defines IOCOTHERTHING _IO('?',7), there really isn't any
> way to prevent that, nor to prevent them from conflicting when - and
> eventually it will happen - someone wants to run a system with both new
> thing and other thing.
>

This is partially enforceable. As once we generate catchall switch like:

case FOO_OP:
...
case BAR_OP:
...

a compiler will report error whenever FOO_OP = BAR_OP.



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