Viewing XATTRS of a doc via cbc

In the cbc release notes it mentions that it supports the LCB_SDCMD_GET_FULLDOC flag, for viewing XATTRS.

However, I don’t see anything in the docs about this and I’m not familiar with cbc.

How do I view the XATTRS for a given doc id? In particular, I was hoping to view system XATTRS, if that makes a difference.

Moved to https://issues.couchbase.com/browse/CCBC-807