Unable to extract audio cd tracks

Polytropon freebsd at edvax.de
Sun Dec 19 14:41:24 UTC 2010

On Sun, 19 Dec 2010 14:41:50 +0100, David Demelier <demelier.david at gmail.com> wrote:
> Thanks,
> The handbook says we must `taste' the media, it works but it prints a 
> warning
> markand at Melon ~ $ dd if=/dev/acd0 of=/dev/null count=1
> dd: /dev/acd0: Invalid argument
> 0+0 records in
> 0+0 records out
> 0 bytes transferred in 0.000132 secs (0 bytes/sec)
> I just realized that using the block size for the same thing works :
> markand at Melon ~ $ dd if=/dev/acd0 of=/dev/null count=1 bs=2352
> 1+0 records in
> 1+0 records out
> 2352 bytes transferred in 2.893379 secs (813 bytes/sec)
> I propose modifying the following :
> http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/creating-cds.html
> Make sure the appropriate files exist in /dev. If the entries are 
> missing, force the system to retaste the media:
> # dd if=/dev/acd0 of=/dev/null count=1 *bs=2352
> Then people who try that won't be surprised by the Invalid argument error.

A good idea - again one step into the right direction
of providing high-quality documentation.

In fact, I have never needed to "taste" the media in my
extraction scripts, but I now do realize WHY: Before using
dd bs=2352 to get the data, I did

	cdcontrol -f /dev/acd0 info

which prints out the TOC of the audio CD and, I assume,
makes sure the corresponding /dev/acd0tNN track files
get created; cdcontrol is part of the base system so it
should be possible to rely on its presence, at least on

Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...

More information about the freebsd-questions mailing list