Minor WED RCS issues, solution provided

I use the RCS hook feature and just noticed that we can change the FNAME var. So we can change the FNAME in BEFORE LOCK and we can get a lock on the requested file+item. YAY

But the original FNAME returns in BEFORE READ, so we need to change it again, and yes the item gets read.

Then when WED has the file+item open and the lock is set on our new file+item, the originally requested file is still displayed in the editor tab.

And on trying to save, the UI goes to open the item again, but it does not fire another BEFORE READ. So it displays a dialog: "Unable to open original_fname".

Looking at the FTBP code I've found that WED always asks for the original IO.FNAME. It's not passed back up to the application.

Also FTSVRSUB is missing code (I'm hesitant the call it a bug but I believe it is) in the AFTER READ hook which resets the variables on returning from the hook. This goes within the IF RCS.VER THEN block:

* TG 2017/06/23 FIX to re-assign fname/rname with TMP vals
IO.FNAME=TMP.FNAME
IO.RNAME=TMP.RNAME

I make the same change to FNAME in BEFORE UPDATE and AFTER UPDATE, but since it never gets there those hooks are never executed.

Also note that in DO.WRITE, there is no RCS hook. Please add a new (RCS V3) ACTION value for BEFORE PREUPDATE so that we can set the IO.FNAME there if required. I don't believe that should call BEFORE UPDATE because that hook assumes the update will actually succeed. It's possible that if this PREUPDATE read fails (which is what caused me to look into this) that BEFORE UPDATE would do something with the assumption that the update was going to succeed, and that would not be correct. The new call should go between GOSUB PARSE.IO.CMD and the check for IO.FNAME=''.

Thanks!