Empty Files Created by sftp

[Chris Rapier]

Oh, I'm sure the correct solution is to just use -R but this just seemed 
weird to me. If it's expected behaviour that's fine.

On 6/30/2026 22:06, Chris Rapier wrote:
> I seem to have a found an odd situation. When the sftp-server is 
> instantiated with "-P write" and I try putting a file I get the expected 
> permission denied error.
> 
> sftp> put xxhash.h
> Uploading xxhash.h to /tmp/xxhash.h
> xxhash.h               98%  255KB 238.9MB/s   00:00 ETA
> write remote "/tmp/xxhash.h": Permission denied
> 
> However, I still get a file created at the destination with a file size 
> of 0.
> 
> rapier@:/tmp$ ls -l xxhash.h
> -rw-rw-r-- 1 rapier rapier 0 Jun 30 21:28 xxhash.h
> 
> So it seems the file was opened but the write was disallowed. The main 
> issue being that it consumes inodes and just generally clutters things 
> up. This can be a real issue on large puts. I haven't tried this against 
> 10.4 so you might have already resolved this.
> 
> I'm pretty sure the issue is that the -P write will prevent the writes 
> but it doesn't match on the open. If you do -P write,open then you can't 
> actually do any reads. I'm digging into a fix but I don't like what I 
> have at the moment. I don't think this would be a common scenario but it 
> came up recently and thought I should bring it up.
> 
> Chris