Re: Making / using CD-RW with CD9660

[Alexander Schreiber <als%thangorodrim.ch@localhost>]

On Sun, Jan 26, 2025 at 02:09:43PM -0500, Todd Gruhn wrote:
> I made and then installed:
> 
> 
> mkisofs -o FOO.iso  -l -J -R -allow-leading-dots  FOO
> 
> when I mount it, it is only readable. I cannot delete or add to this CD.

That is correct. ISO9660 was designed as a read-only filesystem. It is
generated once, written to a suitable medium (i.e. CD-R) and then read.
To update it, you regenerate it again from e.g. a suitable file tree.

> If I do 'df' I see that the fs is 889124 and %Cap==100.

Yes, it is always 100% full. The concept of "free space so one can add
files" doesn't exist in ISO9660.

> How do I get a rw filesystem that is 700MB?

For optical media, that would be UDF. Which is supported by NetBSD,
see newfs_udf(8) and mount_udf(8), but I've never tried it.

Kind regards,
            Alex.
-- 
"Opportunity is missed by most people because it is dressed in overalls and
 looks like work."                                      -- Thomas A. Edison