[hfs-user] To make a Readonly HFS Volume

James Pearson jcpearso@ps.ucl.ac.uk
Fri, 26 Apr 2002 13:25:51 +0100

>I want to make a HFS volume readonly.
>I am setting the flag in mdb.drAtrb to
>mdb.drAtrb | = 0x4000 ( As said in Inside Macintosh)
>Bit    Meaning
>15      Set  if th volume is Locked by Software.
>After creating a Image of such a Volume.
> I am mounting it with a FreeWare application in Windows which can mount HFS
> But , I can still add files to that volume through this
>  software and delete them too.
>  That shows the volume is not Locked.
>  So, anything else I should do to Volume parameters
>  to make that Volume represent a ReadOnly one??

mkisofs (mkhybrid) makes a volume readonly using:

mdb.drAtrb |= HFS_ATRB_SLOCKED

where HFS_ATRB_SLOCKED is defined as (1 << 15) == 0x8000

Of course, this still assumes that whatever is mounting the volume honours the
readonly flag ...

James Pearson