Re: Distinct transactions (MV vs rename())?

[Theodore Tso <tytso mit edu>]

On Tue, Sep 11, 2001 at 05:20:44PM -0700, KRELLE,BRIAN (HP-Roseville,ex1) wrote:
> Another thread on July 26th about MTAs and metadata synchronization,
> cryptically titled "ext3-2.4-0.9.4", talked about rename() being atomic
> in regards to other processes attempting to open the file being renamed.
> 
> Since MV, or LN, do not seem to use the rename() function, how does one
> accomplish step 6 above atomically from processes using the FS API?  It
> would also be nice to minimize the number of underlying filesystem 
> transactions to be powerfail safe.

As near as I can tell mv seems to use the rename() function, as long
source and target are on the same filesystem.  If the source and
destination directories are on different filesystems, then a copy
followed by an unlink will take place.

							- Ted