Re: sshx protocol from MS Windows occasionally cuts off results in M-x rgrep

[Michael Albinus]

Michael Albinus <michael.albinus@gmx.de> writes:

Hi Jim,

>> This is an odd issue, and I'm not sure what's happening yet: sometimes
>> when calling `M-x rgrep' or other similar commands, I don't see all
>> the results I'd expect. I'm consistently able to reproduce the bug but
>> it only appears rarely, so it usually requires refreshing the rgrep
>> buffer repeatedly until I get unlucky:
>>
>>   * Start emacs from an MS Windows client
>>   * Open tramp/info/dir remotely:
>>     `C-x C-f /sshx:server:~/src/tramp/info/dir'
>>   * rgrep for "info" in all files of tramp/info:
>>     `M-x rgrep RET info RET RET RET'
>>   * There should be 72 results (as of commit f00e5853)
>>   * Switch to the rgrep buffer and hit g to refresh it repeatedly
>>   * Every so often (maybe 5% of the time), fewer than 72 results are
>>     returned(!)
>
> FTR, I could reproduce it. Don't know what's the reason, but it is a start.

I've played with this for some hours. The missing grep hits are always
the hits from the end, meaning that the output of the remote process
does not arrive completely.

When this happens, Tramp is already out of the game. It has prepared the
*grep* buffer, and it has started the remote grep process. Arrival of new
output of the remote process is out of Tramp control.

Like you, I could reproduce it only with Tramp's sshx on Windows 10, not
with plinkx. So I guess it is a problem of the Windows ssh client, that
it doesn't show all output if a remote process has exited. Some
buffering problems?

Unfortunately, I have no idea how to check further. Hmm.

>> Thanks,
>> - Jim

Best regards, Michael.