Is there a program to log clipboard activity

[David Goodenough]

I have a need to log all clipboard activity on a Linux system.  I googled
and did not find anything (I suspect I was asking the wrong question).

I did find the xclipboard program which displays all activity, so I guess
it would not be hard to modify it to log the activity to file, but I would
rather reuse than reinvent so I wondered if anyone has already written such
a program which was generally available.

David