[Coco] No easy rename on OS-9 ?

[Johann Klasek]

On Mon, Mar 31, 2014 at 12:44:20PM -0400, billg999 at cs.uofs.edu wrote:
> >
> > I'm afraid that you are missing the historical lineage of OS9.  OS9 was
> > meant to be a "small computer" version of UNIX as was OS9's sister system,
> > some unknown operating system called "Linux".  In UNIX, MV was born as a
> > copy source to destination, then delete source so that is exactly the way
> > it is done in OS9!  (and Linux).  Contact the creators of UNIX to find out
> > why they did their programming in the way that they did.
> 
> I hate to burst your bubble, but that is just not true.  I just looked
> at the source for mv in Ultrix-11 V3.1 which is a DEC derivative of AT&T
> Version 7 Unix dating back to at least 1984 and what it does is:
> 1) determine if source is a directory then it can only rename, not move
> 2) attempts to link source and destination if this fails use "/bin/cp"
> 3) unlink source

Right, my old Coherent 3.2 (System 7) behaves like this, too.
Can be easily proven by looking at the i-node which is preserved in case
of a rename on the same filesystem.
Modern systems have file utilities which do this for directory
objects, too. Historically not supported on most old-style Unixes.