Re: newfs_udf(8) and other OSes

[Benny Siegert <bsiegert%gmail.com@localhost>]

On Sat, Jun 27, 2015 at 6:47 PM,  <tlaronde%polynum.com@localhost> wrote:
> Since the ntfs-3g(8) driver has very poor performance with USB (and the
> bottleneck is the driver, since formatting and using the device as an
> UDF one the writing performance, even if not tremendous, is improved)
> I'm trying to find if UDF can be used as a common filesystem to
> allow to read---here---the same USB connected disk both under NetBSD
> and under Windows.

Interesting idea!

> What is different is that the Windows selects 2048 bits as block size,
> while newfs_udf is setting 512 bits.

newfs_udf allows setting "blocking size" and sector size with the -B
and -S options. Maybe there is a combination of these that Windows
will like?

> Furthermore, fdisk(8) shows no MBR

Did you write on the "d" device, i.e. the whole thing? Windows and Mac
OS prefer to have an MBR and partition table on a USB stick, as they
consider it the same as a hard drive. However, see below.

> when using newfs_udf(8) while the Windows formatted shows the first
> pseudo partition as a 238 aka "GPT Protective MBR".

So the stick has a GPT partition table, not an MBR. You will want to
use gpt(8) to create one. (I would be interested in knowing which GPT
partition type Windows uses for the GPT partition.) Something like

gpt create sd0
gpt add -t windows sd0

then detach and reattach the stick for the partition table to be recognized.


Good luck!