[geeks] Weird MacOS issue

[Jonathan C. Patschke]

On Tue, 23 Dec 2008, Mark Benson wrote:

> Okay I'll first of all spell this out to anyone who's listening. You
> should *never* install anything else at the same time as an OS X main
> update, particularly AFTER one.

This is not a big deal on OS X 10.5, as updates which require a reboot are
deferred until a reboot to be installed themselves--so long as they're
installed from Software Update, as opposed to manually from the combo
image.  Even in that case, having an OS update partially installed doesn't
preclude you from running other installations.

> I always quit everything, install the update then reboot immediately. OS
> X updates *used* to lock you out from running any more apps after you
> ran them. I don't know if that's still the case.

No, because Apple either quit messing with the AppKit and Foundation
version numbers at point updates, or made the runtime version check for
the system frameworks less paranoid than they used to be.

> Still, they set up a lot of stuff, especially in 10.5.x, that runs at
> reboot and if you run anything that disrupts that you can wave bye-bye
> to your OS working.

Not true.  I run plenty of updates that require reboots, and defer the
reboot until I actually have the time to reboot.  We're well past the
System 7 days of System-file resource updates, "tidbits" patches, code
fragments, and all the other nonsense that made the OS so fragile.

System Updates aren't magical voodoo.  They're file copies.  I've never,
in my entire history of running this OS for 6 years, made time to reboot
immediately after a point-upgrade unless the partially-installed update
prevented me from finishing whatever I was working on.  I've also never
broken a Mac by doing so.

> It then boots a second time to return to the OS X desktop. I've never
> booted it in Verbose to see what it does during that process but I
> suspect it boots a minimal OS image and patches the OS's kernel and
> essential system files to the latest version, then resets the boot
> parameters to boot the full OS.

It's nothing quite so dramatic--this is Unix, after all.  The system boots
into single-user mode, runs a script to finish whatever it could not do
while WindowServer was running prior to the reboot, requickstarts (I can't
recall the Darwin term for library address fixups) the contents of
/usr/lib and registered frameworks, patches the EFI boot image with driver
changes, and reboots.

> I'd go with the FAT corruption being a definite issue too, you could
> also fix it by dropping it in a Windows box and putting a Windows MBR on
> it then dropping it back in the Mac and re-initializing it as a Mac
> disk.

FAT corruption will not affect OS X's root filesystem (as was the original
complaint), as OS X's root filesystem cannot be a FAT filesystem.  OS X is
perfectly capable of laying down and obliterating both FATs and MBRs from
Disk Utility; there's no need to get Windows involved if you really want
to do that.

-- 
Jonathan Patschke < "There is great satisfaction in building good tools
Elgin, TX          > for other people to use."
USA               <                                     --Freeman Dyson