Re: [MdeModulePkg/TerminalDxe] Why do we delay 2s for ESC being pressed?

[Heyi Guo <heyi.guo@linaro.org>]

On 11/08/2017 05:07 PM, Gerd Hoffmann wrote:
> On Wed, Nov 08, 2017 at 04:44:37PM +0800, Heyi Guo wrote:
>>
>> 在 11/8/2017 4:34 PM, Ni, Ruiyu 写道:
>>> No.
>>> Even a terminal tool can recognize F10, it still needs to translate it into "ESC [ V"
>>> and send the three bytes to firmware.
>> Got it. But the 2 seconds timeout is not for this situation, right? If
>> terminal tool could translate and send the key sequence, I think it can
>> complete 3 bytes transfer in a very short time, isn't it? E.g. 9600 baud / 8
>> = 1200 Bytes/s (ignore control bits).
>>
>> So 2 seconds timeout is still for user to enter the sequence "ESC [ V"
>> manually?
> No.  Alot of software has this kind of delay because it is recommended
> in some classic unix documentation to avoid mis-interpreting incomplete
> terminal control sequences coming from slow terminals.
>
> Where a "slow terminal" which actually would need such a long delay is a
> physical terminal from the 70ies of the last century, or a virtual
> terminal hooked up over a *really* slow network connection.
>
> Reducing the delay from 2 seconds to roughly 0.2 seconds should be
> pretty safe, things are not that slow any more these days :)
That will be great if we can make such change :)

Thanks,

Heyi

>
> HTH,
>    Gerd
>