[ydl-gen] Re: HFS+ mount is read only -- how to make RW? (YDL 4.0.1)

[Jeffrey Paul Burger]

Red Alert! Now I've lost access to my HFS+ drive from both Linux and OS X!!!
Help!!!

Background: This is a dual boot G5 running YDL 4.0 and OS 10.4. I'm a Linux
newbie. A friend (who no longer lives where I do) gave me the magic to mount
the Mac OS disk from YDL at /dev/sdb, so that's the destination I've been
using. And I have a "macos" folder in my mnt directory. Until now, I've been
successfully mounting and reading from the HFS+ drive using "mount /dev/sdb
/mnt/macos -t hfsplus". (Strangely, until I corrected it today, the exec
file my friend wrote was missing a space:  "... -thfsplus" and it still
mounted and read.) Anyway, the problem came when trying to follow
instructions from this thread to enable writing to the HFS+ disk from YDL as
well.

Pursuant to earlier messages in this thread, I found hfsplus on my system
and invoked in. The man page essentially says:

hpmount [...] source-path

Not knowing whether source-path meant /mnt/macos or /dev/sdb, I tried both.
I know that hpmount /dev/sdb gave me the following message (hpmount
/mnt/macos may have been identical but I can't be sure now):

"Warning. You are about to open /dev/sdb for writing. Are you sure you want
to do this (y/n)?"

I responded affirmatively and received:

"hpmount: Neither wrapper nor native HFS+ volume header found (unknown error
4294967295)"

I went ahead anyway with the usual "mount /dev/sdb /mnt/macos -t hfsplus"
and received:

"Wrong fs type, bad option, bad superblock on /dev/sdb or too many mounted
filesystems"

After trying several variations on this theme (and getting the same error
messages), I decided to see if I could boot from that volume normally under
OS X. After the initial switch screen for Linux vs. OS X, followed by the
gray Apple logo on the white screen, the logo is replaced with a large gray
international symbol for "no" (circle with a slash across it). And the
circular progress meter below just spins forever.

So I now have two problems: 1) how do I get my OS X boot drive back? 2) what
did I do wrong (or what do I need to do right) to access this drive from YDL
once it's resurrected?

Any and all help is greatly, greatly appreciated. And please keep in mind
that I only know enough to make myself dangerous (obviously!) and clear
explanations are very helpful.

Thank you!

Jeffrey