Re: Synchronous signal delivery..

Randy.Dunlap
2003-02-15T01:05:58Z

On Sat, 15 Feb 2003 01:01:53 +0000
Jamie Lokier <jamie@shareable.org> wrote:

| Davide Libenzi wrote:
...
| >
| > Hmm ... using read() you'll lose the timeout capability, that IMHO is
| > pretty nice.
|
| Very good point.
|
| Timeouts could be events too - probably a good idea as they can then
| be absolute, relative, attached to different system clocks (monotonic
| vs. timeofday). I think the POSIX timer work is like that.

Hi Davide, Jamie-

Yep. And there are people (plural :) who would still like to get
that patch accepted into 2.5 too....

| It seems like a good idea to be able to attach one timeout event in
| the same system call as the event_read call itself - because it is
| _so_ common to vary the expiry time every time.
|
| Then again, it is also extremely common to write this:
|
| gettimeofday(...)
| // calculate time until next application timer expires.
| // Note also race condition here, if we're preempted.
| read_events(..., next_app_time - timeofday)
| // we need to know the current time.
| gettimeofday(...)
|
| So perhaps the current select/poll/epoll timeout method is not
| particularly optimal as it is?

--
~Randy