whats the plot

so i went through and tried to back-tag all the posts on the site… more difficult than it sounds, especially since i was at a loss as to how to tag some of the things (especially in a consistent manner). i am not showing a tag cloud yet, but maybe soon ™.

i’ve also added links to my twitter and flickr in the sidebar. i guess i should start looking into some wordpress plugins at some point in the near future for some of the stuff in the sidebar.

*update* – tried showing a tag cloud, but i don’t really like it… things i don’t care about surfacing get surfaced because they end up being “bucket” categories and things i do care about don’t :p

i like the tagging so i can have, for example, snippets as the tag for all the posts that have code snippets in them, and pictures as the tags for all posts that have pictures in them, and so on… but i guess kind of like del.icio.us, if i think about the correctness and consistency of my tags too much, it starts to bother me :p

generally speaking, my set of mp3s is very well tagged. for my personal mp3s, i used to exclusively use easytag to tag them, and now i use a combination of easytag and amarok (which is totally awesome by the way!)

but sometimes, i have to mass edit id3tags for mp3s on the server, and i don’t have the luxury of using such gui tools for the editing. as thus, i’ve been mainly using id3v2 within some perl scripts to tag mp3s. this turns out to work great, but i also wanted to be able to add album art to the mp3s from the command line.

i couldn’t figure out how to do it using id3v2 (perhaps using the custom frames, there’s a way, but nothing extremely simple and obvious from what i was looking at). then i found the solution in the form of a id3lib-ruby, a ruby wrapper for id3lib, the same library that id3v2 is based on.

with this, everything turns out to be extremely easy -

require 'id3lib'

tag = ID3Lib::Tag.new('myfile.mp3')
cover = {
   :id => :APIC,
   :mimetype => 'image/jpeg',
   :picturetype => 3,
   :data => File.read('cover.jpg')
}

tag << cover
tag.update!

and that’s it. nice and simple. by the way, a picturetype of 3 denotes a front cover and is the default value (just learned that from a quick search). oh and the output mp3 image cover shows up fine in both linux and on itunes. beautiful!

so i was working on some code in which i needed to know whether or not it was dst for a given country and/or timezone or not. luckily, with php5.2, some sparsely documented (yet very useful) classes were introduced – a more thorough documentation can be found here.

so let’s say i want to know whether or not egypt is in dst right now or not… so first i need to know what zoneinfo file egypt uses (for egypt, it’s simple, but this trick is useful for more obscure places, like “isle of man,” for example):

cd /usr/share/zoneinfo
grep -i egypt iso*.tab        # get the iso country code for egypt

# the above command returns 'EG' - so...
grep EG zone.tab
# returns 'Africa/Cairo'

in many cases, there are many timezones that exist for a given country. in many cases, it’s obvious which file you need, but in some cases, it’s not very obvious. in those cases, i found it helpful to open the binary files and look at the very last line, in which some hint about the offset of the timezone is given.

anyway… once you have the zoneinfo file that you would use, it’s very easy to find whether or not you are in dst (well, assuming that you know what the standard, non-dst offset from utc is). for example:

$tz = new DateTimeZone('America/New_York');
$date = new DateTime();
$date->setTimezone($tz);
echo $date->;format(DATE_RFC3339) . "\n";
echo $date->getOffset()/3600 . "\n";

running this returns the time in new york, and the offset (-4). since the standard est offset is -5 hours, -4 means we’re +1 which means we are currently on dst.

so if you don’t know the standard offset, another trick that you could do is pass some parameters to the new DateTime() constructor – so for example…

$tz = new DateTimeZone('America/New_York');
$date = new DateTime('2008-12-31');
$date->setTimezone($tz);
echo $date->getOffset()/3600 . "\n";

this returns -5, which is out of dst. anyhow, you could use the above if you don’t know the default offset for a timezone for dst by passing in 2 dates – something towards the middle of the year (july-ish) and something towards the end of the year (december-ish). if the offsets are different, the place probably has dst.

also, do note that some places have things a little differently – so dst in windhoek, namibia, for example, ends in april and starts in september.

thanks to the iwphone wordpress plugin, the blog now looks a lot better on the iphone!

speaking of the iphone, i am really disappointed at the notion that the long awaited sdk coming out on 3/6 will potentially be locked down. i guess we can’t know for sure until the announcement on thursday, but i personally have gone ahead and re-jailbroken my phone, courtesy of zibri’s ziphone.

i always used to get upset when i send a message or set a status on an english site in arabic, only to have the punctuation all messed up. well, thanks to two unicode control characters, \u200e and \u200f (for ltr and rtl, respectively), i can finally go from writing:

يحيى الإسلام!

to writing:

يحيى الإسلام!‏

much better thanks goes to this wikipedia article and adil allawi, whom i first heard about this from.