Re: behavior of overwriting running executables?

Barry Lagerweij (
Thu, 16 May 1996 14:07:51 +0200 (MET DST)

On Thu, 16 May 1996, Alan Cox wrote:

> > SGI's Irix allows the program to be overwritten, but causes the running
> > program to core-dump !
> Does this apply to overwriting setuid programs (say with correct code so it
> doesnt core dump ?). Thats one of the side issues of not locking processes
> you are paging off.

Regardless of the setuid bit, a program that has been overwritten will
core-dump in about 90% of the occasions. Since it does not occur on each
occasion, it seems to be a paging problem. Anyway, I think Linux'
solution is much cleaner. It still allows you to unlink & cp, so you can
update say a cgi-bin while the webserver is still running.