Fwd: Re: [vox-tech] debian woody to sarge upgrade = dead xserver: solved

[Peter Jay Salzman]

On Thu 26 Aug 04,  3:04 PM, Ken Bloom <kabloom at ucdavis.edu> said:
> On Thu, 26 Aug 2004 14:33:09 -0700
> Rick Moen <rick at linuxmafia.com> wrote:
> > About SIG11 errors:  Most often, signal 11 indicates RAM defects (89%
> > of the time), or CPU problems including overheating (1%).  Let's say
> > as a vague handwave that the other 10% are defective software.  Since
> > Ashleigh wasn't getting SIG11s _before_ he upgraded, one suspects
> > software.  Thus my "chuck X11 out completely, including --purge to
> > snag conffiles, and refetch X11 packages; and, if that doesn't work,
> > snag the unstable branch's packages" bit.
> 
> I don't think that's correct. Signal 11 is better known as SIGSEGV, and
> it is a segmentation fault usually caused by a programmer dereferencing
> an uninitialized pointer (or a deleted pointer). It's entirely a
> programmer error.
 
almost always.  here, kenbloomsprogram segfaults, even though it was
perfectly written:

killall -9 kenbloomsprogram    ;-)


but in all seriousness, a segfault is a signal sent to a process upon
accessing memory it doesn't have access to or in a way it's not permitted to.

it's true that a segfault is not "caused" by hardware.  but it's also true
that a segfault is not "caused" by dereferencing an uninitialized pointer
either.

it simply is an incorrect access of memory, whether that access is brought
about by dereferencing a null pointer or faulty hardware.

so you both are correct.

pete