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Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

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Lepl parser for Python.

Colorless Green.

Photography around Santiago.

SVG experiment.

Professional Portfolio

Calibration of seismometers.

Data access via web services.

Cache rewrite.

Extending OpenSSH.

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Using iPod on Linux

From: andrew cooke <andrew@...>

Date: Sat, 11 Aug 2012 13:06:49 -0400

I foolishly thought this would be easier than it was...  The iPod in question
is a new 160GB classic.

First, I read about Linux support for HFS (the Mac file system).  It seems now
to be working, as long as journalling is disabled, so I initialised the iPod
using Paulina's Mac (that formats the internal drive to HFS).  My theory was
that HFS would give better performance and perhaps longer battery life than
FAT.

Note that you need to explicitly disable journaing from a Mac, otherwise Linux
will mount the disk in read-only mode.

I then wrote some code that generated a database from my music and used the
Python wrappers to libgpod to load a random selection to the iPod.

This code failed to work.  I never understood why.
http://stackoverflow.com/questions/11777914

The gtkpod program (which is also based on libgpod) does work, however.  So I
adopted my code to generate a directory of links to random tracks.  I then
used gtkpod to load those tracks to the iPod.

The interface to gtkpod is less than intuitive.  Somehow I managed to lose an
important window and spent 30 minutes desperately clicking around.  But
eventually you can get it to work.

That worked once.

The second time I tried it there were errors and my computer crashed.

The third time I watched more closely and the HFS driver is throwing errors.
Again the computer (my desktop, which has the music) eventually crashed.  It
seems that the HFS support in Linux is still unreliable.

So I decided to try using iTunes from within a virtual machine (VirtualBox).
I already had a VM running Windows on the desktop for development work.

I exported my music using Samba, which I could see from Windows.  I then
installed iTunes.  But then I found that Windows could not see the USB hub
(even when the Oracle extension is installed).  I believe this is either
because my hardware is USB3, or because I was using the "open source" version
of VirtualBox (which comes with OpenSuse).

So I then installed the Oracle version of VierualBox on my laptop.  This did
work with USB (using WINdows 7 32 bit).  So I installed iTunes and reformatted
the iPod to FAT (windows disk format).

With that, gtkpod on my desktop (which is where the music is) appears to be
working.  If it fails the next step is to mount the music over samba on the
network to my laptop and use iTunes to load the music from Windows.

I guess at some point I should just check that the issue with libgpod and
Python was not FS-related (ie check that the code still fails with FAT).  I am
pretty sure that is the case, since gtkpod worked (until the kernel/FS
failed), but I should check.

For now, however, I really can't be bothered.  What a frustrating pile of crap
(even when it works, loading 100GB of music over USB2 takes hours...)

Andrew

It Gets Worse

From: andrew cooke <andrew@...>

Date: Sat, 11 Aug 2012 13:34:18 -0400

gtkpod is pretty much unusable once the iPod is full.  It is glacially slow
and sometimes hangs completely (no CPU use and a dead GUI).

Andrew

Switched to RockBox

From: andrew cooke <andrew@...>

Date: Wed, 15 Aug 2012 10:09:25 -0400

I gave up and switched to RockBox (think "installing Linux on iPod" for the
general idea).

At first it looked *awful*.  But fiddling with the settings you can get a very
minimal white-on-black character-only display, that basically looks like
you've got a command line interface.  "Now playing" shows some dynamic level
bars, but no album cover.  It actually look spretty cool in an old-school way.

And you can load files directly to the file system.  It just works.

Assuming I don't find any deal-breakers I will update the ypod code to work
with this.

Andrew

To Install Latest RockBox on iPod Classic

From: andrew cooke <andrew@...>

Date: Fri, 17 Aug 2012 09:10:56 -0400

Follow the emcore instructions at
http://www.freemyipod.org/wiki/EmCORE_Installation/iPodClassic but for the
final step unzip the "development builds" from
http://www.rockbox.org/wiki/IpodClassicPort

You can also update from the original (emcore) to development by simply
unpacking over the existing files (I was told this on IRC and just tried it
and it appears to work).

One reason to do this is that this bug may have been fixed -
http://www.rockbox.org/tracker/task/12729

Andrew

Copying to FAT32

From: andrew cooke <andrew@...>

Date: Wed, 19 Sep 2012 18:32:21 -0300

Copying files from Linux to FAT32 is non-trivial if you've named the files
according to ID3 tags.  The following command renames characters correctly:

  pax -vrwL -s '/[?<>\\:*|\"]/_/gp' source dest

Credit:
http://superuser.com/questions/178025/linux-copy-to-fat32-filesystem-invalid-argument

(with -L to copy across soft links)

Andrew

Alternate Substitution

From: andrew cooke <andrew@...>

Date: Sun, 5 May 2013 01:37:47 -0400

pax -vrwL -s '/[^A-Za-z0-9 \/\.\-]\+//gp' source dest

Is better for files with "foreign" characters.

Andrew

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