problems with bzr 0.10 and paramiko sftp transfer

[Robey Pointer]

On 31 Aug 2006, at 10:21, John Arbash Meinel wrote:

> Lukáš Lalinský wrote:
>> John Arbash Meinel wrote:
>>> Lukáš Lalinský wrote:
>
> ...
>
>> I've just experienced the same problem on my server. In my local  
>> branch all the
>> .kndx files start with "# bzr knit index 8\n\n", but if I push the  
>> branch using
>> the sftp transfer (paramiko 1.6.2), the headers get removed. After  
>> downgrade to
>> paramiko 1.6.1 it pushed the branch correctly (though the one on  
>> server was
>> damaged, so I had to do delete it and push all revisions).  
>> Unfortunately this is
>> probably too deep in the source code for me to debug it...

I just reproduced this and it turns out to happen only for paramiko  
dev, not 1.6.2.

The sad news is that it's the append behavior we were hoping to  
optimize away: posix doesn't ignore an lseek() on an append-only  
file, and openssh's sftp server code always does the lseek.  I  
thought I'd tested against openssh but clearly not well enough.

John, this means I'll have to revert the optimization and paramiko  
will still have to do a round-trip to fetch the file length before  
appending to a file.  That probably makes your patches to avoid  
appending more important.

robey