Tech
Moving the blog to PAX
2020-05-05 -- After more than five years of silence, I may be resurrecting my old blog. I already got as far as rewriting it using MGL-PAX, which is a curious choice because PAX is a documentation generator for Common Lisp. The blog "engine" is rather bare-bones but works admirably, especially considering that the implementation is only 72 lines of code, most of which deals with post categories and overview pages with shortened posts, something PAX hasn't seen the need for.
Hung Connections
2011-02-27 -- My ISP replaced a Thomson modem with a Cisco EPC3925 modem-router to fix the speed issue I was having. The good news is that the connection operates near its advertised bandwidth, the bad news is that tcp connections started to hang. It didn't take long to find out that this particular router drops "unused" tcp connections after five minutes.
The fix recommended in the linked topic (namely sysctl'ing
net.ipv4.tcp_keepalive_time
& co) was mostly effective but I had
to lower the keepalive to one minute to keep my ssh sessions alive.
The trouble was that OfflineIMAP connections to the U.S. west coast
still hanged intermittently while it could work with Gmail just
fine.
In the end, OfflineIMAP had to be patched to use the keepalive and the keepalive be lowered to 15s:
sysctl -w net.ipv4.tcp_keepalive_time=15 \
net.ipv4.tcp_keepalive_intvl=15 \
net.ipv4.tcp_keepalive_probes=20
Oh, and always include socktimeout
in the offlineimap config, that's
more important than keepalive unless you never have network issues.
OfflineIMAP with Encrypted Authinfo
2011-02-26 -- I've moved to an
OfflineIMAP + Gnus
setup that's outlined at
various
places.
Gnus can be configured to use
~/.authinfo as a
netrc style of file to read passwords from and can easily use
encrypted
authinfo
files as well. Offlineimap, on the other hand, offers no such
support and passwords to the local and remote imap accounts are
normally stored in clear text in .offlineimaprc
.
For the local account this can be overcome by not running a dovecot server but making offlineimap spawn a dovecot process when needed:
[Repository LocalGmail]
type = IMAP
preauthtunnel = /usr/sbin/dovecot -c ~/.dovecot.conf --exec-mail imap
For the remote connection, ideally it should read the password from
.authinfo.gpg
that Gnus may also read if it's configured to access
the remote server directly. This can be pulled off rather easily.
Add an /include/ to .offlineimaprc
like this:
[general]
pythonfile = ~/.offlineimap.py
where ~/.offlineimap.py
just defines a single function called
get_authinfo_password
:
#!/usr/bin/python
import re, os
def get_authinfo_password(machine, login, port):
s = "machine %s login %s password ([^ ]*) port %s" % (machine, login, port)
p = re.compile(s)
authinfo = os.popen("gpg -q --no-tty -d ~/.authinfo.gpg").read()
return p.search(authinfo).group(1)
Now, all that's left is to change remotepass to something like this:
remotepasseval = get_authinfo_password("imap.gmail.com", "username@gmail.com", 993)
Of course, .authinfo.gpg
should also have the corresponding entry:
machine imap.gmail.com login username@gmail.com password <password> port 993
That's it, no more cleartext passwords.
Upgrade Woes 2
2010-02-08 -- Debian Squeeze finally got Xorg 7.5 instead of the old and dusty 7.4. The upgrade was as smooth as ever: DPI is off, keyboard repeat for the Caps Lock key does not survive suspend/resume and the trackpoint stopped working. Synaptics click by tapping went away before the upgrade so that doesn't count.
Upgrade Woes
2009-11-06 -- Debian Lenny was released back in February. My conservativeness only lasts about half a year so I decided to upgrade to Squeeze aka Debian testing. The upgrade itself went rather smoothly with a few notable exceptions. With KDE 4.3 I should have waited more.
Notes:
Who thought it a grand idea that in the default theme (Oxygen) the color of the panel and window title bar cannot be customized? Installing the desktop theme called Aya solved the panel issue while going back to Keramik helped with the title bar.
The kmail message list is a train wreck by default with its multi-line entries. It took me ages to find how to turn it to back to classic theme (hint: it's not under `Configure KMail'), at the cost of no threading messages.
I had customized kwin to use the Super key for all shortcuts. KDE3 decided to call it the Win key, but hey, I understand that's where it's often mapped. After the upgrade my settings were wiped out.
In org-mode
C-u C-c C-t
had asked for a new tag. After the upgrade and(setq org-use-fast-todo-selection 'prefix)
it does so again.The X.org upgrade broke my fragile xmodmap config so I wrote an xkb based config instead. It's activated with:
xkbcomp -I$HOME/.xkb ~/.xkb/keymap/us_lisp $DISPLAY
Upgrading to emacs23 was painless, except for blorg that needed a couple of hacks to get this entry out the door.
Space Cadet
2008-12-15 -- Emacs users often report problems caused by strain on the pinky finger that's used to press the Control key. The standard answer to that is to map Caps Lock to Control. I believe that there is a better way:
Note the placement of modifiers: Control, Meta, Super, Hyper on both sides of Space in this order, with Control being the closest to it. Touch typers especially find having two of each key absolutely essential and the symmetric placement appeals to me.
... read the rest of Space Cadet.
Backup
2008-03-28 -- My carefully updated list of files to backup had grown so long that it made me worry about losing something important and the backup didn't fit on a single dvd so I invested in a WD passport and created an encrypted file system on it:
modprobe cryptoloop
modprobe aes
losetup -e aes /dev/loop0 /dev/sdb
mke2fs /dev/loop0
tune2fs -i 0 -c 0 -j /dev/loop0
... read the rest of Backup.
First post
2008-02-01 -- After a long time of waiting to write my own blog software like true hackers with infinite time do (and those irritated by Wordpress), I bit the bullet and installed blorg - a very low overhead emacs blog engine - on top of org-mode that I happen to use as an organizer. Blorg basically converts an org mode buffer to html files so it is completely static: send me email if you have comments, I have no desire to maintain a more complex solution with comment filtering.
Small fixes had to be made for blorg to be able to deal with org-mode 5.17a and I only had time to bring it to some basic level of functionality. That said here is the blorg-init.el file I'm using right now.
2020-05-03: Since then, this blog has been moved to MGL-PAX.