On Thu, Jun 25, 2015 at 09:49:58AM +0000, Chen, Hanxiao wrote:
 How about:
 
 errcode = ENOTSUP;
 
 reply_with_error_errno (errcode, " btrfs filesystems' UUID cannot be
changed");
 
 Then we got the errno, and set_uuid could tell whether we support this feature. 
Seems that would make sense, yes.
Rich.
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