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

[Jan-Erik Söderholm]

Den 2021-05-25 kl. 14:28, skrev Arne Vajhøj:
> On 5/25/2021 8:09 AM, Simon Clubley wrote:
>> On 2021-05-24, Arne Vajhøj <arne at vajhoej.dk> wrote:
>>> 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.
>>
>> It's unexpected because most people are not going to find the one
>> paragraph deep in a low-level programmer's manual that documents this.
>>
>> They are going to look at other documentation sources where this very
>> unexpected behaviour is not documented.
> 
> VSI already stated that they will update the DCL documentation to also
> reflect that.
> 
>>> I agree.
>>>
>>> Not only is it what's there.
>>>
>>> As it turned out then it is actually documented behavior.
>>>
>>> Actual behavior is expected to follow documented behavior.
>>>
>>> It is almost guaranteed that there will be some functionality
>>> where ones expectation without reading the documentation is
>>> different from actual behavior.
>>>
>>
>> This is the documented behaviour that most people are going to read:
>>
>> ---------------------------------------------------------------------------
>> READ
>>
>>    /TIME_OUT
>>
>>          /TIME_OUT=n
>>          /NOTIME_OUT (default)
>>
>>       Specifies the number of seconds after which the READ command is
>>       terminated if no input is received. If you enter the /TIME_OUT
>>       qualifier, you must specify a value from 0 to 255.
>>
>>       If you enter both the /ERROR=label and /TIME_OUT qualifiers, and
>>       the time limit expires, the error branch is taken.
>> ---------------------------------------------------------------------------
>>
>> That text is simple, clear to understand, and completely wrong.
> 
> It is not wrong. It is incomplete.
> 
> Arne
> 

And besides, how many realy do care about this?