trinity-devel@lists.pearsoncomputing.net

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Month: April 2012

Re: [trinity-devel] sftp-kio - still fails in R14 - Any progress? (log captured - may help?)

From: "Timothy Pearson" <kb9vqf@...>
Date: Mon, 23 Apr 2012 02:44:35 -0500
>>>> On 04/22/2012 10:36 PM, Timothy Pearson wrote:
>>>>> I just tested on my Debian Squeeze system with OpenSSH_5.5p1 and
>>>>> OpenSSL
>>>>> 0.9.8o, and sftp from GIT worked perfectly.  I am going to try a
>>>>> newer
>>>>> system to see if I can get it to fail.
>>>>>
>>>>> Tim
>>>>>
>>>>
>>>> Note, sftp from konsole will work PERFECTLY. It is sftp:// from the
>>>> konqueror
>>>> address field, or kwrite/kate that fails. Here is the debug output for
>>>> a
>>>> box
>>>> that does not use key-pairs for authentication:
>>>
>>> I know. :-)  I am tracing the issue now, but it appears that ssh > 5.5
>>> somehow masks its stderr output so that TDE literally does not know
>>> what
>>> ssh is doing.
>>>
>>> Tim
>>
>> To be more precise, it looks like select() is not blocking on the ssh
>> output file descriptors.  This could also be a kernel or core system
>> issue, so stay tuned! :-)
>>
>> Tim
>
> I have narrowed this down to a problem in how ssh and select() are
> interacting.  To be specific, running select() on the open ssh output file
> descriptor always returns data available, but when an attempt is made to
> actually read said data with read() there is no data (an error occurs).  I
> do not know if this is an ssh problem or a problem with some other aspect
> of the system regarding pipes.
>
> Tim

Fixed (hacked around) in GIT hash e72f492.  Basically select() no longer
works on newer systems (could be due to a malfunction of some kind, but it
doesn't really matter), so instead of busywaiting on select(), newer
systems will busywait on read().

Tim