[Info-vax] DCL "READ/TIME_OUT=n" from terminal; timer resets if message written to screen

[Stephen Hoffman]

On 2021-05-25 00:03:44 +0000, Arne Vajhj said:

> On 5/24/2021 7:53 PM, Dave Froble wrote:
>> On 5/24/2021 2:12 PM, Simon Clubley wrote:
>>> On 2021-05-24, David Jones <osuvman50 at gmail.com> wrote:
>>>> I imagine read/time_out=... is using the timeout feature of the terminal driver
>>>> and not timer ASTs. The timeout is a feature of the wait for interrupt function
>>>> in the kernel, which is why it resets for every character entered (as well as
>>>> breakthru writes).
>>> 
>>> _If_ that is the case, then the read timeout functionality is broken 
>>> IMHO because that is _very_ unexpected behaviour.
>> 
>> I don't agree with what you wrote.  Yes, I'd prefer a bit different 
>> operation, but, I can understand and accept what's there.  Maybe could 
>> be better, but, not broken.
> 
> I agree.
> 
> Not only is it what's there.
> 
> As it turned out then it is actually documented behavior.

For those that know the undocumented and internal implementation 
details of READ /TIMEOUT, sure.

That's, um, well, that's just not documented in the DCL manual. At all.

But then this is OpenVMS, and we can always find some obscure 
justification for preserving the existing and variously some patently 
absurd behavior.

Not that the startup, the installers, and related parts of OpenVMS 
don't (also) need to be rethought and reworked, but that's unlikely to 
happen this decade.




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