[Bug-tar] Tar hangs (blocks?) on existing file when extracting with `--skip-old-files` and `--xattrs`.

[Dawid]

Hi,

I've tried to use `tar + ssh + tar` pipeline to copy files between two 
hosts. The only twist over many examples you can find with 2 minutes of 
online searching is that I need to copy `xattrs` and not overwrite the 
existing files.


To my surprise it worked the first time, but on subsequent attempts it 
just hangs. After some investigation, it turned out that if one uses 
`--xattrs --skip-old-files` together, and `tar x ...` encouter existing 
file, it just hangs.


More investigation (when looking for workaround) revealed that 
`--keep-old-files` does not seem to preserve `xattrs` of the 
destination. The original destination file will be kept, but the xattrs 
will be overwritten anyway.


I've tested with tar 1.27.1 on Ubuntu 14.04.1, and please excuse me if 
there's not that much details given, but I'm in the middle of something, 
so I'm just shooting a quick email so I won't forget.


Regards,

Dawid