Quadruple boot YDL, Gentoo PPC, Mac OS X, Mac OS 9???

[Tim Seufert]

On Sunday, July 20, 2003, at 01:31  PM, David Orlovich wrote:

> Something I've been wondering about - if I format my HD partitions as 
> UFS then can both OSX and various Linux distros all read these 
> partitions?  I'm thinking only OS9 would not be able to ... is this an 
> option?  Cheers, David O.

Linux:  can mount UFS readonly (I believe the write support is 
experimental).  You have to track down the right mount flags because 
the OS X version of UFS is different.  (Each BSD tends to have its own 
private UFS variant.)

OS X:  It is usually not a good thing to use UFS for an OS X boot 
partition.  Some OS X software won't work at all when installed on UFS, 
and the OS X UFS implementation is for legacy purposes only (read: it's 
slow).  HFS+ really is the native OS X filesystem.

OS 9:  Can mount HFS/HFS+, cannot mount UFS at all.

In the end, the best thing is usually to dedicate a small (1 gigabyte 
is small on today's HDs!) partition for data transfer, and format it 
with the least common denominator FS that every OS can safely read and 
write.  Right now that means formatting it as plain HFS.  Safe use 
under Linux implies use of the hfstools package (hmount, hcopy, etc.) 
instead of actually mounting the HFS partition.  The Linux HFS 
filesystem implementation is known to be buggy (hasn't had a real 
maintainer for years) and may corrupt the HFS partition and/or cause 
kernel panics.  Lots of people get away with using it anyways because 
usually it doesn't screw up if you only do a couple simple things and 
then unmount; just warning you that in your mental map you should mark 
it as "Here be Dragons".

Once the new Linux HFS+ filesystem has been tested and integrated and 
makes its way into YDL, you can switch the exchange partition to HFS+ 
and mount it in Linux normally.  (Or, you can do that right now if you 
want to install a new kernel with the HFS+ patch.)  You could also 
mount your main OS X partition, but personally I'd not mount it 
read/write until confident that there aren't any corrupting bugs in the 
HFS+ implementation.  (It's a young piece of code and HFS+ is a tricky 
FS to implement.)