on 7/31/00 6:29 AM, Lex Spoon at lex at cc.gatech.edu wrote:

> Tim Rowledge <tim at sumeru.stanford.edu> wrote:
>>> I like the concept of time stamps.
>> So do I, unless it costs a lot - although keystroke and mouse button
>> events are usually relatively slow (ie maybe a couple of hundred aminute
>> at worst) some events (people have been considering serial or
>> socket events for example) might be much higher bandwidth and could
>> cause a problem if getting the time is costly. Something to keep an eye
>> on; some OSs provide timestamps on event, some don't. Some have
>> expensive clock() calls, some are cheap. We have to check and make sure
>> we don't make life good on one platform by ruining it on another, just
>> like always.
>> 
>> 
> 
> Hmm, I just put these two ideas together.  On Unix, the timestamps for X
> events are going to be based on a completely separate clock from the
> ones for sockets.  I guess the VM can just stamp the times itself, and
> ignore whatever X says, but something is definately lost: the input
> events will be less precise!
> 
> The alternatives on Unix seem to be:
> 
> 1. Only use *input events*, and allow for precise timings.
> 2. Mix all events into the same queue, but use imprecise timings.
> 
> 
> 
> -Lex
> 
Someone was mentioning the expensive cost of doing timestamps on the mac,
well perhaps indirectly. David Simmons at Camp Smalltalk mentioned to me a
way he used in QKS smalltalk to get microsecond timing very very cheaply.
I'll look into exploring this option.

PS I'm not sure I understand why the clock for sockets on Unix is different
than the one from X?

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