(import requests)
 
(setv req (requests.get "http://hy.pault.ag"))
(if (= req.status_code 200)
  (for (kv (.iteritems req.headers))
    (print kv))
  (throw (Exception "Wrong status code")))

('date', 'Wed, 03 Apr 2013 12:09:23 GMT')
('connection', 'keep-alive')
('content-encoding', 'gzip')
('transfer-encoding', 'chunked')
('content-type', 'text/html; charset=utf-8')
('server', 'nginx/1.2.6')

If it is the first download, the maintainer creates a new git repository. If it has been packaged before, he clones the repository. The important point here is that this is not the upstream repository, it is an independent repository for Debian packaging.

• For historical reasons that are continuingly vanishing in importance, Debian fetishises the tarballs produced by upstream. While upstreams increasingly consider them an unimportant distraction, Debian insists in hoarding and rolling around in on its nest of gleaming pristine tarballs. I wrote pristine-tar to facilitate this behavior, while also pointing fun at it, and perhaps introducing a weak spot with which to eventually slay this particular dragon. It is widely used within Debian. .. Anyway, the point is that it's no problem to import upstream's tarball into a clone if their git repository. It's fine if that tarball includes files not present in their git repository. Indeed, upstream can do this at release time if they like. Or Debian developers can do it and push a small quantity of data back to upstream in a branch.
• Sometimes tagged releases in upstream git repositories differ from the files in their released tarballs. This is actually, in my experience, less due to autotools generated files, and more due to manual and imperfect release processes, human error, etc. (Arguably, autotools are a form of human error.) When this happens, and the Debian developer is tracking upstream git, they can quite easily modify their branch to reflect the contents of the tarball as closely as they desire. Or modify the source package uploaded to Debian to include anything left out of the tarball. My favorite example of this is an upstream who forgot to include their README in their released tarball. Not a made up example; as mentioned tarballs are increasingly an irrelevant side-show to upstreams. If I had been treating the tarball as canonical I would have released a package with no documentation.
• Whenever Debian developers interact with upstream, whether it's by filing bug reports or sending patches, they're going to be referring to refs in the upstream git repository. They need to have that repository available. The closer and better the relationship with upstream, the more the DD will use that repository. Anything that pulls them away from using that repository is going to add friction to dealing with upstream. There have, historically, been quite a lot of sources of friction. From upstreams who choose one VCS while the DD preferred using another, to DDs low on disk space who decided to only version control the debian directory, and not the upstream source code. With disk space increasingly absurdly cheap, and the preponderance of development converging on git, there's no reason for this friction to be allowed to continue.

brew tap petere/postgresql
brew install postgresql-9.2
# etc.
brew install --HEAD postgresql-common

pg_createcluster 9.2 main
pg_ctlcluster 9.2 main start
pg_lsclusters

• homebrew-postgresql
• postgresql-common homebrew branch

• Throughout the GNOME documentation and tools, "schema", "key" and "path" are used nearly interchangeably to mean roughly the same thing. (I think a path describes a key within a schema, to be precise.)
• schemas/keys/paths "must start with and end with a forward slash character", except when they mustn't, such as in override files, where you must use a dot, and you don't prefix or suffix the schema/key/path with dots. In fact the command line gsettings tool only accepts dotted schemas, not slash-separated ones.
• Sometimes, people choose XML, and save themselves the trouble of writing a custom parser, but at the expense of ease for humans having to read or write files. gsettings uses XML for schema files, but a separate ini-style format for override files. Everybody wins?
• glib-compile-schemas requires a path argument, so all your schema and override files must be in the same place. Sites have to lump stuff into /usr/share/glib-2.0/schemas alongside distribution files, rather than separated out to (say) /usr/local/share/glib-2.0/schemas.
• It's quite possible to get an override file past glib-compile-schemas which non-the-less is broken. The result is gsettings clients, including the gsettings binary itself, complaining and then segfaulting. Do not rely on glib-compile-schemas to ensure compliant override files.
• glib-compile-schemas would appear to read override files in native byte order, so make sure you name your override so that it sorts after any distribution-provided overrides. E.g., 20_my_gnome-shell.gschema.override to sort after 10_gnome-shell.gschema.override.

• there is brand recognition there from when I lived in Canberra and used ActewAGL
• it looks like I can sign up online without having to talk to anyone (as soon as my damn mobile phone number ports over to Internode and starts working)
• they're first on the list of electricity retailers

Manually setting up an encrypted root partition Before setting up the synchronization between the two drives, I had to replicate the partition setup. I used fdisk, cfdisk and gparted to create the following partitions:

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *        2048      499711      248832   83  Linux
/dev/sdb2          501760   500117503   249807872    5  Extended
/dev/sdb5          503808   500117503   249806848   83  Linux

and then loosely followed these instructions to create an encrypted root partition on /dev/sdb5:

$ cryptsetup luksFormat /dev/sdb5
$ cryptsetup luksOpen /dev/sdb5 sdb5_crypt
$ pvcreate /dev/mapper/sdb5_crypt
$ vgcreate akranes2 /dev/mapper/sdb5_crypt
$ vgchange -a y akranes2
$ lvcreate -L247329718272B -nroot akranes2
$ lvcreate -L8468299776B -nswap_1 akranes2
$ mkfs.ext4 /dev/akranes2/root

Finally, I added the new encrypted partition to the list of drives to bring up at boot time by looking up its UUID:

$ cryptsetup luksUUID sdb5_crypt

and creating a new entry for it in /etc/crypttab.

Copying the boot partition Setting up the boot partition was much easier because it's not encrypted. All that was needed was to format it and then copy the files over:

$ mkfs.ext2 /dev/sdb1
$ mount /dev/sdb1 /mnt/boot
$ cp -a /boot/* /mnt/boot/

The only other thing to remember is to install grub on the boot loader of that drive. On modern Debian systems, that's usually just a matter of running dpkg-reconfigure grub-pc and adding the second drive (/dev/sdb in my case) to the list of drives to install grub on.

Sync scripts To keep the contents of the SSD and the hard drive in sync, I set up a regular rsync of the root and boot partitions using the following mount points (as defined in /etc/fstab):

/dev/mapper/akranes-root /           ext4    noatime,discard,errors=remount-ro 0       1
/dev/mapper/akranes2-root /mnt/root  ext4    noatime,errors=remount-ro         0       2
UUID=0b9109d0-... /boot              ext2    defaults                          0       2
UUID=6e6f05fb-... /mnt/boot          ext2    defaults                          0       2

I use this script (/usr/local/sbin/ssd_boot_backup) for syncing the boot partition:

#!/bin/sh
if [ ! -e /mnt/boot/hdd.mounted ] ; then
    echo "The rotating hard drive is not mounted in /mnt/boot."
    exit 1
fi
if [ ! -e /boot/ssd.mounted ] ; then
    echo "The ssd is not the boot partition"
    exit 1
fi
nice ionice -c3 rsync -aHx --delete --exclude=/ssd.mounted --exclude=/lost+found/* /boot/* /mnt/boot/

and a similar one (/usr/local/sbin/ssd_root_backup) for the root partition:

#!/bin/sh
if [ ! -e /mnt/root/hdd.mounted ] ; then
    echo "The rotating hard drive is not mounted in /mnt/root."
    exit 1
fi
if [ ! -e /ssd.mounted ] ; then
    echo "The ssd is not the root partition"
    exit 1
fi
nice ionice -c3 rsync -aHx --delete --exclude=/dev/* --exclude=/proc/* --exclude=/sys/* --exclude=/tmp/* --exclude=/boot/* --exclude=/mnt/* --exclude=/lost+found/* --exclude=/media/* --exclude=/var/tmp/* --exclude=/ssd.mounted --exclude=/var/lib/lightdm/.gvfs --exclude=/home/francois/.gvfs /* /mnt/root/

To ensure that each drive is properly mounted before the scripts run, I created empty ssd.mounted files in the root directory of each of the partitions on the SSD, and empty hdd.mounted files in the root directory of the hard drive partitions.

Cron jobs The sync scripts are run every couple of hours through this crontab:

10 */4 * * *                root    /usr/local/sbin/ssd_boot_backup
20 0,4,8,12,16,20 * * *     root    /usr/local/sbin/ssd_root_backup
20 2,6,10,14,18,22 * * *    root    /usr/bin/on_ac_power && /usr/local/sbin/ssd_root_backup

which includes a reduced frequency while running on battery to avoid spinning the hard drive up too much.

Don't say we should open-source the code. That would be a nightmare! And I have limited confidence in APIs. LibraryThing has the book geeks, but not so much the computers geeks.

When trying to use types other than image/png , authors can check if the image was really returned in the requested format by checking to see if the returned string starts with one of the exact strings data:image/png, or data:image/png; . If it does, the image is PNG, and thus the requested type was not supported. (The one exception to this is if the canvas has either no height or no width, in which case the result might simply be data:, .)

If the type requested is not image/png, and the returned value starts with data:image/png, then the requested type is not supported.

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John Harrison was featured in Only Fools & Horses, as the designer of the watch that made Delboy & Rodney millionaires. ->Time on our hands