sed page 20 - Dave's Blog

Backup Notes

2007 Jul 13, 8:30I bought an external backup drive a few weekends ago. I've previously setup a Subversion repository so I decided to move everything into the repository and then back it up. So in went the contents of all of my %USERPROFILE% and ~ directories with a bit of sorting and pruning. Not too much though given its much easier to dump in everything and search for what I want then to take the time to examine and grade each file. What follows are the notes I took while setting this up. It takes me a bit of time to look up the help on each command so I figure I'll write it all down here for the benefit of myself and potentially others...

Setting Up the Backup Drive For Linux
I first changed the filesystem on the drive to ext3. I plugged it into my USB2.0 port and ran fdisk:

sudo fdisk /dev/sda

Useful commands I used to do this follow mostly in order:

m

help

p

print current partitions

d

delete current partition

n

create new partition (I used the defaults)

w

write changes and exit

Then I formatted for ext3.

sudo mkfs.ext3 /dev/sda1

I made it easy to mount:

sudo vim /etc/fstab
# added line to end:
/dev/sda1 /media/backup ext3 rw,user,noauto 0 0

I setup the directory structure on the disk

mount /media/backup
sudo mkdir /media/backup/users
sudo mkdir /media/backup/users/dave
sudo chown dave:dave /media/backup/users/dave

After all that its easy to make a copy of the Subversion repository:

mount /media/backup
cp -Rv /home/dave/svn /media/backup/users/dave/
umount /media/backup

Next on the agenda is to add a cron job to do this regularly.

Subversion Command Reference
On a machine that has local access to the Subversion repository you can check out a specific subdirectory as follows using the file scheme:

svn co file:///home/dave/svn/trunk/web/dave%40deletethis.net/public_html

Note also that although one of my directories is named 'dave@deletethis.net' Subversion requires the '@' to be percent-encoded.
Other useful subversion commands:

svn help

help

svn list file:///home/dave/svn/

list all files in root dir of svn depot

svn list -R file:///home/dave/svn/

list all files in svn depot

svn list -R file:///home/dave/svn/ | grep \/$

list all directories

svn status

List status of all files in the working copy directory as in - modified, not in repository, etc

svn update

Brings the working copy up to date wrt the repository

svn commit

Commit changes from the working copy to the repository

svn add / move / delete

Perform the specified action -- occurs immediately

Setting up Windows Client for Auto Auth into SVN
When using an SVN client on Windows via svn+ssh its useful to have the Windows automatically generate connections to the SVN server. I use putty on my Windows machines so I read the directions on using public keys with putty.

putty.exe dave@deletethis.net
cd .ssh
vim authorized_keys # leave the putty window open for now
puttygen.exe
Click the 'generate' button
Move the mouse around until finished
Copy text in 'Public key for pasting into OpenSSH authorized_keys file:' to putty window & save & close putty window
Enter Key passphrase & Comment in puttygen
Save the private key somewhere private
pageant.exe
'Add Key' the private key just saved.

Checking out using Tortoise SVN
On one of my Windows machines I've already installed Tortoise SVN. Checking out from my SVN repository was really easy. I just right clicked in Explorer in a directory and selected "SVN Checkout...". Then in the following dialog I entered the svn URI:

svn+ssh://dave@deletethis.net/home/dave/svn/trunk/web/dave%40deletethis.net/public_html/

Note again that the '@' that is part of the directory name is percent-encoded as '%40' while the '@' in the userinfo is not.

Windows Command Line Check Out
On my media center I didn't want to install Tortoise SVN so rather I used the command line tool. I setup pageant like before the only difficulty was getting the SVN command line tool to use putty. With the default configuration you can use the SVN_SSH environment variable to point at a compliant SSH command line tool. The trick is that its interpreted as a backslash escaped string. So I set mine thusly:

set SVN_SSH=C:\\users\\dave\\bin\\putty\\plink.exe

The escaping solved the vague error I received about not being able to create the tunnel.backup technical personal windows svn linux subversion

Second Life Translator

2007 Jul 4, 10:58Hackdiary
I really enjoy reading Matt Biddulph's blog hackdiary. An entry some time ago talked about his Second Life flickr screen which is a screen in Second Life that displays images from flickr.com based on viewers suggested tags. I'm a novice to the Second Life scripting API and so it was from this blog post I became aware of the llHTTPRequest. This is like the XMLHttpRequest for Second Life code in that it lets you make HTTP requests. I decided that I too could do something cool with this.

Translator
I decided to make a translator object that a Second Life user would wear that would translate anything said near them. The details aren't too surprising: The translator object keeps an owner modifiable list of translation instructions each consisting of who to listen to, the language they speak, who to tell the translation to, and into what language to translate. When the translator hears someone, it runs through its list of translation instructions and when it finds a match for the speaker uses the llHTTPRequest to send off what was said to Google translate. When the result comes back the translator simply says the response.

Issues
Unfortunately, the llHTTPRequest limits the response size to 2K and no translation site I can find has the translated text in the first 2K. There's a flag HTTP_BODY_MAXLENGTH provided but it defaults to 2K and you can't change its value. So I decided to setup a PHP script on my site to act as a translating proxy and parse the translated text out of the HTML response from Google translate. Through experimentation I found that their site can take parameters text and langpair queries in the query like so: http://translate.google.com/translate_t?text=car%20moi%20m%C3%AAme%20j%27en%20rit&langpair=fr|en. On the topic of non US-ASCII characters (which is important for a translator) I found that llHTTPRequest encodes non US-ASCII characters as percent-encoded UTF-8 when constructing the request URI. However, when Google translate takes parameters off the URI it only seems to interpret it as percent-encoded UTF-8 when the user-agent is IE's. So after changing my PHP script to use IE7's user-agent non US-ASCII character input worked.

In Use
Actually using it in practice is rather difficult. Between typos, slang, abbreviations, and the current state of the free online translators its very difficult to carry on a conversation. Additionally, I don't really like talking to random people on Second Life anyway. So... not too useful.personal translate second-life technical translator sl code google php llhttprequest

Wiimote wiissues

2007 Jun 7, 5:29The other day I had the best idea for my Wii remote. Clearly I should use it to control the rotation of Tetris pieces in my N-dimensional Tetris game Polytope Tetris. One of the issues I described with Polytope Tetris is user input. Given a Wii remote the user could rotate a piece through 3 dimensions in a manner that's much easier to adjust to than particular keys on the keyboard.

Anyway, I did a little research into how this might work. I knew that the Wii remote used infrared for absolute positioning and Bluetooth for everything else (LEDs, speaker, accels.) I bought a Bluetooth adapter for my PC after realizing that none of my computers had one already. I used GlovePIE to ensure that my Wii remote could connect and successfully communicate with my computer. GlovePIE is actually pretty cool -- it provides a simple script layer over the Wii remote to control things like your mouse.

Since Polytope Tetris is in Java I looked for and found a Java library for operating with the Wii remote and a long forum thread discussing its use. I then read up on Bluetooth in Java. Apparently JSR 82 is the name of the standard that describes the API a Bluetooth stack should expose in Java. That is, to get Bluetooth working in Java one needs an additional package for Java that actually implements the Bluetooth Java API. This package would depend on the system so I suppose I can't fault Sun for not including it... Where to find such a package? I found a comparison list of implementations and tried the ones that support javax.bluetooth. None of them worked for me because none can address USB devices it seems or they cost money and I couldn't get the trial version working. I also tried bluesock (not listed on the previous list) which seemed promising and could produce an address for my Wii remote as a connected device but couldn't use that address.

And I thought that after I found the Wii remote Java library it would be easy... Oh well...java bluetooth wii technical remote jsr82 tetris polytopetetris wiimote

IE7 Feed Display Update

2007 May 22, 3:22I've created an update to the IE7 feed display.

After working on my update to the XML source view I tried running my resourcelist program on other IE DLLs including ieframe. I found that one of the resources in ieframe is the XSLT used to turn an RSS feed into the IE7 feed display.

My first thought for this was that I could embed enclosures into the feed display. For instance, have controls for youtube.com videos or podcast audio files directly in the feed display. However, I found that I can't use object or embed tags that rely on ActiveX controls in the page or in frames in the feed display.

With that through I decided I could at least add support for some RSS extensions. Thanks to IE7's RSS platform which provides a normalized view of RSS feeds it was really easy to do this. I went to several popular RSS feeds and RSS feeds that I like and took a look at the source to see what extensions I might want to add support for.

For digg.com I added support for their RSS extension which includes digg count, and submitter name and icon. I added the digg count in a box on the right and tried to make it fit in stylistically. For the iTunes RSS extension I add the feed icon, feed author, and descriptions. I was surprised by how much of the podcasts content was missing from the feed view. I also added support for a few other misc things: the slash RSS extension's section and department, the feed description to the top of the feed display, and the atom author icon.

I wonder what other goodies lurk in IE's resources...feed res slashdot digg resource itunes technical browser ie rss extension

XPointer Framework - IE7 XML Source View Upgrade Part 3

2007 May 17, 5:16Previously I created some resource tools and then I used them to overwrite msxml3's XML source view. In this update I've added support for the XPointer Framework.

This time around I've started to add support for the XPointer Framework to my XML source view and I've added installation instructions. The framework consists of a series of pointer segments each of which has a scheme name followed by data in parenthesis. For example 'scheme1(data1)scheme2(data2)scheme3(data3)'. A pointer segment resolves to a portion of the XML document based on the data and the scheme name. The whole pointer resolves to the first segment that successfully resolves. That is, from the example, if scheme1 resolves to nothing and scheme2 resolves to something then that's used and scheme3 is ignored. In addition to the framework I've added support for the xmlns scheme which binds namespace prefixes to a namespace URI and the element scheme which is a simple way to resolve to particular elements in an XML. I also have limited support for the xpointer scheme the content of which is resolved as an XPath with some extra functions (which I don't support -- hence the limited). I've also thrown in schemes for the two SelectionLanguage values supported by msxml3.

Next time I might try to support the xpointer functions that aren't in xpath using msxml script. But I think I'm losing steam on this project... we'll see.resource technical xml xpointer res xpath xslt

Sculpture Garden

2007 May 15, 8:38Last Saturday Sarah and I went to the Sculpture Garden in Seattle. Its laid out with exhibits all outside running down to the water.

Sarah and I followed the trail of sculptures down to the shore and took some more photos on the sand and rocks on the mini beach. There's also a green house but it was closed the day we were there. The glass of the green house is tinted green and the long walls of the house slope down in the back giving a forced perspective to the viewer on one end.

The sculptures aren't roped off rather they mingle with the normal urban artifacts. There are little signs around that politely ask viewers not to touch the art for fear of damage that reminded me of the show Arrested Development.sculpture washington personal art seattle nontechnical

MoHo Living

2007 May 13, 12:16My parents and grandmother came to visit the weekend before this current weekend, starting Friday May 4th. They arrived via their new motor-home which is quite the machine. Of course its my parents motor-home so its very well decorated inside including drapes and mini-chandelier. I didn't have a memory card for my camera at the time but I'm sure my parents will put up photos on their new blog dedicated to their motor-home at some point in the future.

At any rate, they parked the motor-home in an RV park in Issaquah so that Friday night I drove over to them and we ate at the conveniently closely located Pogachas. The next day they came over and I showed them the various cool looking things my computer connected to my flat screen TV can do. This includes Vista Media Center showing my photos from recent trips and Google Earth mapping out our respective homes and my recent trips (and Paris). Additionally, we played Wii which, unsurprisingly based on anecdotal evidence from varied sources across the Internet, was a seeming hit. Mom broke records playing bowling with my dad and I, Dad did an excellent job fishing, and Grandma's slow but steady win's the race approach to cow racing worked very well.

The next day I drove them to Seattle and we walked around Pike's Place. My parents made dinner that night at my place which was very good and made my apartment actually smell like cooked food. Also, we exchanged Christmas gifts. For the past two years I've flown back to my parents' house for Christmas and ended up with gifts I couldn't take with me in both directions. Those I left at their house they drove up and I was able to give them the ones I left at my place. They started the drive back the next day. I really enjoyed seeing them here.motorhome family personal nontechnical

New XSLT - IE7 XML Source View Upgrade Part 2

2007 May 11, 8:55Last time, I had written some resource tools to allow me to view and modify Windows module resources in my ultimate and noble quest to implement the XML content-type fragment in IE7. Using the resource tools I found that MSXML3.DLL isn't signed and that I can replace the XSLT embedded resource with my own, which is great news and means I could continue in my endevour. In the following I discuss how I came up with this replacement for IE7's XML source view.

At first I thought I could just modify the existing XSLT but it turns out that it isn't exactly an XSLT, rather its an IE5 XSL. I tried using the XSL to XSLT converter linked to on MSDN, however the resulting document still requires manual modification. But I didn't want to muck about in their weird language and I figured I could write my own XSLT faster than I could figure out how theirs worked.

I began work on the new XSLT and found it relatively easy to produce. First I got indenting working with all the XML nodes represented appropriately and different CSS classes attached to them to make it easy to do syntax highlighting. Next I added in some javascript to allow for closing and opening of elements. At this point my XSLT had the same features as the original XSL.

Next was the XML mimetype fragment which uses XPointer, a framework around various different schemes for naming parts of an XML document. I focused on the XPointer scheme which is an extended version of XPath. So I named my first task as getting XPaths working. Thankfully javascript running in the HTML document produced by running my XSLT on an XML document has access to the original XML document object via the document.XMLDocument property. From this this I can execute XPaths, however there's no builtin way to map from the XML nodes selected by the XPath to the HTML elements that I produced to represent them. So I created a recursive javascript function and XSLT named-template that both produce the same unique strings based on an XML node's position in the document. For instance 'a3-e2-e' is the name produced for the 3rd attribute of the second element of the root element of the XML document. When producing the HTML for an XML node, I add an 'id' attribute to the HTML with the unique string of the XML node. Then in javascript when I execute an XPath I can discover the unique string of each node in the selected set and map each of them to their corresponding positions in the HTML.

With the hard part out of the way I changed the onload to get the fragment of the URI of the current document, interpret it as an XPath and highlight and navigate to the selected nodes. I also added an interactive floating bar from which you can enter your own XPaths and do the same. On a related note, I found that when accessing XML files via the file URI scheme the fragment is stripped off and not available to the javascript.

The next steps are of course to actually implement XPointer framework parsing as well as the limited number of schemes that the XPointer framework specifies.xml xpointer msxml res xpath xslt resource ie7 technical browser ie xsl

San Francisco Trip

2007 May 11, 7:48After Carissa and Elijah's wedding Sarah and I went to San Francisco. We drove in, well Sarah drove anyway, still in the PT Cruiser Sunday morning and checked into our hotel, Hotel Diva. I was originally concerned that I wouldn't fit in as I don't really consider myself a diva, however the hotel was cool. They have Internet rooms setup in various themes, the front desk is always staffed, our room had a very modern look, and when we entered the flat-screen over the front desk was playing an episode of Aqua Teen Hunger Force.

We walked around a bit before going to the SF Museum of Modern Art. There was a Picasso exhibit at the time which we could see for only $3 more. It felt kind of wrong like my ticket was super-sized. I think the most memorable piece I saw was three white panels which consisted of three blank panels. Art. Sure. After that Sarah wanted to see the giant Hello Kitty store she had heard of from her sister. We ended up going to the Westfield Shopping center which has a disappointingly average sized Hello Kitty store. Apparently the giant one is gone. That night we went to First Crush for dinner. I had a flight of wine which consists of three one-third sized glasses of various but complimentary wines. It was a great restaurant in terms of food, drink, atmosphere and service.

The next morning we were even more the tourists when we went down to Fisherman's Wharf and Pier 39. We visited the famous wax museum and purchased multiple pounds of taffy. On the way back to the Oakland airport we got to experience a little traffic as part of the 580 freeway had collapsed the morning we arrived and was still under repair on our way out. We survived of course and I think the trip went rather well.sanfrancisco personal california sfmoma nontechnical

Movie Times

2007 May 1, 3:48The Sunday of the weekend before last I had friends over and we watched Antitrust and Sneakers. Watching Antitrust makes me wonder if Bill Gates has seen it. Tim Robbins plays a character that is essentially based on him but so over the top that its ridiculous.

A few days before that I watched The Prestige with Sarah. I can't tell if I was or wasn't supposed to know what was going on until the end but it was cool anyway. I didn't know until later but David Bowie plays Tesla which is just awesome all the way around.

We also watched The Illusionist sometime before. Both movies are adaptations of novels with stage magicians set in turn of the century England. And I enjoyed both of them. I thought one would be a rushed attempt by one studio to compete with the another on the same ground but that doesn't seem to be the case. I've noticed this before with those asteroid disaster movies and the two movies about Truman Capote. It turns out Wikipedia has a huge list of competing similar movies.personal movies nontechnical