Re: Security question: "Text file busy" overwriting executables but not shared libraries?

Alexander Viro
2001-10-15T11:50:59Z

On Mon, 15 Oct 2001, Jamie Lokier wrote:

> This does not work. Example:
>
> 1. JamieEmacs loads file using MAP_PRIVATE.
> 2. Something else writes to the file.
> 3. Scroll to the bottom of the file in JamieEmacs. It displays some
> of the newly written data, though not all of it.
>
> --> Wrong editor semantics.

--> Wrong permissions or hopelessly crappy source control system.

At point 2 you are _already_ screwed. Depending on who hits (hell,
what's the equivalent of :x in Emacsese?) first, one of you is
going to lose results of editing. Doctor, it hurts when I do it...

If you want versioning - use source control system. Or go play
with DEC cra^WOSes. In RSX that "feature" sucked (and so did
editor semantics, but that's a separate story).

Without versioning - see above.