Mark Mielke wrote:
> It looks fine to me for as long as we can guarantee that sizeof(void *)
> will be less than or equal to sizeof(__uint64_t) (relatively safe).
It is fine, for epoll itself, even if sizeof(void *) > sizeof(__uint64_t).
Conversion functions for legacy 32-bit code running on a 128-bit chip
will be more complex, but epoll is the _least_ of problems in that case...
> I still prefer 'userdata' over 'obj', but the name of thing is not very
> important to me.
The AIO subsystem has a very similar cookie, which is simply declared
as `__u64 aio_data' in user-supplied requests, and returned in the
responses. It's converted to a field called `ki_user_data' in the
kernel.
Just a few reference points... I like `user_data' myself.
> I'm not sure if this is wise or not, but an 'fd' member might be
> useful as well:
> [...]
> For applications that wish to store fd's (probably common due to
> poll() roots), this would help them avoid casting magic as well. Also,
> it allows for 64 bit file descriptors if that ever became necessary.
That is a good idea, if we go for the union.
-- Jamie
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This archive was generated by hypermail 2b29 : Sat Nov 23 2002 - 22:00:34 EST