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

[David Jones]

On Monday, May 24, 2021 at 10:04:49 AM UTC-4, Dave Froble wrote:
> There is the speculation that the timer AST was queued to allow time for 
> user entry. That might not always be the case. Likely on a read from 
> terminal in DCL. 
> 
> My "normal" usage of timer ASTs is that I want to allow some time for 
> something to happen, and if it doesn't, move on. No speculation on 
> anything, just stop waiting and move on.
> -- 

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).