windows-to-windows openssh buffering issue

[Larry Hall (Cygwin)]

On 6/19/2011 4:36 AM, Nathan Ridge wrote:
>
> On Sat, 18 Jun 2011 23:31:12, Larry Hall wrote
>
>> On 6/18/2011 5:25 AM, Nathan Ridge wrote:
>>
>>> On Fri, 17 Jun 2011 11:52:35, Larry Hall wrote:
>>>
>>>> On 6/16/2011 10:20 PM, Nathan Ridge wrote:
>>>>
>>>>> Is there some setting for OpenSSH on the server side that would allow
>>>>> me to run the program on machine B in native-windows non-pty mode
>>>>> so that the buffering is fine? If not, what else can I do?
>>>>
>>>> No. OpenSSH uses ptys - it doesn't matter what terminal or console you're
>>>> using. I don't know of a way to make OpenSSH behave the way you want it to
>>>> with Windows console programs.
>>>
>>> Is this issue particular to OpenSSH, or is ssh-ing into to a windows machine
>>> a lost cause in general?
>>>
>> Since non-Cygwin executables don't understand ptys, they think they are
>> dealing with a pipe and so they buffer their output.  It's not specific
>> to OpenSSH.  You'd see the same issue running these programs under xterm
>> or mintty.  I personally wouldn't define anything about this particular
>> issue as a "lost cause" but YMMV.  Quite some time ago there was an attempt
>> to smooth out this issue with a utility call ttyfier but it had it's issues
>> and has pretty much disappeared.  I don't know of any other aids out there,
>> though that doesn't mean there isn't something .  The only things I can
>> suggest are that you make sure there's not some Cygwin utility that does what
>> you want or that you write something that does.
>
> What I meant was, is it possible to write a different SSH server implementation
> for windows - perhaps a native one - that doesn't suffer from this problem?
> (And if so, do you know of one?) Or would all attempts at an SSH server
> implementation run into this issue?

ptys are a means to an end.  They are not a requirement to implement SSH
or anything else for that matter, if that's what you're asking.  I'm not
aware of many other SSH implementations on Windows.  MKS and SFU each
have one.  I haven't used them though.

-- 
Larry

_____________________________________________________________________

A: Yes.
 > Q: Are you sure?
 >> A: Because it reverses the logical flow of conversation.
 >>> Q: Why is top posting annoying in email?

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