Re: Disk Device API: Some semantical questions

Since I failed to reply all when I sent the original copy of this 
message a minute ago, and since our trusty list is back in action, I'm 
reposting it here. Sorry to Ingo for getting two copies... :-)
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On 2003-07-08 at 10:28:25 [-0700], Ingo Weinhold wrote:
[...determining BDiskDevice::IsReadOnly()...]
> Mmh, our
> DriveSetup would have no way of checking whether it can work on the
> device (i.e. initialize partitions or the device itself) -- other than
> opening the device manually and do a B_GET_DEVICE_GEOMETRY ioctl, of
> course. 

Couldn't it just try to open the device read-write?

On 2003-07-08 at 10:28:25 [-0700], Ingo Weinhold wrote:
> I would at least add a BDiskDevice::DeviceFlags() (we already
> have BPartition::Flags()), which would comprise this and other flags.

Which other flags?

On 2003-07-08 at 14:35:43 [-0700], Ingo Weinhold wrote:
> On Tue, 08 Jul 2003 22:31:07 +0200 CEST "Axel Dörfler" <axeld@pinc-
> software.de> wrote:
> > "Ingo Weinhold" <bonefish-CFLBMwTPW48UNGrzBIF7/[email protected]> wrote:
> > [...]
> > > > > > > name?)? Then IsReadOnly() for any partition would be the
> > > > > > > logical OR of BDiskDevice::IsReadOnlyMedia() and the
> > > > > > > non-write capability of the disk system.
> > > > > > Hm, I don't know if the user might be interested in the
> > > > > > general
> > > > > > write capabilities of a given disk device.
> > > > > Well, at least it doesn't harm, and for the kernelland
> > > > > structures
> > > > > I
> > > > > will definitely discriminate between the two semantically
> > > > > different
> > > > > `read-only's or risk confusion. :-)
> > > > I think that sounds like a good idea, and yes, I think that's
> > > > what
> > > > IsReadOnly() was really intended to convey. Do we need a
> > > > BDiskSystem::IsReadOnly() then, though?
> > > You mean what I named BDiskSystem::IsReadOnlyMedia()? Mmh, our
> > > DriveSetup would have no way of checking whether it can work on 
> > > the
> > > device (i.e. initialize partitions or the device itself) -- other
> > > than
> > > opening the device manually and do a B_GET_DEVICE_GEOMETRY ioctl,
> > > of
> > > course. I would at least add a BDiskDevice::DeviceFlags() (we
> > > already
> > > have BPartition::Flags()), which would comprise this and other
> > > flags.
> > 
> > BTW my question originally aimed at the "OR" part of the first 
> > quoted
> > paragraph. If it's interesting for the user if the disk system has
> > write capabilities or not, it should not be ORed with
> > IsReadOnlyMedia()
> > but be separately accessible.
> 
> Mmh, I guess, I find it more convenient, if BPartition::IsReadOnly()
> does the OR. The information the caller is interested in, is probably
> whether they can modify the partition's contents. The info whether the
> disk system in general does support writing or not is perhaps better
> provided via something like BDiskSystem::IsReadOnly().

That's why I suggested it 4 replies ago. :-) :-P At any rate, I like 
the OR-semantics for BPartition::ReadOnly() as well.

-Tyler