Re: 2.4 and 2GB swap partition limit

Andreas Ferber
2001-04-30T21:31:14Z

Hi,

On Mon, Apr 30, 2001 at 03:14:25PM -0400, Richard B. Johnson wrote:

> > mv /wherever/exeimage /usr/bin/exeimage
[...]
> > This is also basically how things like libc get installed.
> > A single mv is not only preserves currently referenced contents,
> > it is atomic.

One restriction: /wherever and /usr/bin must be on the same partition,
otherwise the mv will be the same as "rm /usr/bin/exeimage && cp
/wherever/exeimage /usr/bin/exeimage && rm /wherever/exeimage", which
is for sure not atomic.

> Sure, but now you can't get back if the new software doesn't run.
> This is why I recommended the two steps and cautioned about testing
> the new stuff first.

Then create a hardlink first, to keep a backup _and_ atomically
replace the file.

Andreas
--
Build a system that even a fool can use and only a fool will want to use it.