Peng.u.i.n

Do 0.8.2 Released!

noreply@blogger.com (Peng) — Tue, 30 Jun 2009 04:23:16 PDT

After 3 months of work, now here is the 0.8.2 release of our beloved GNOME Do!

With this release, a lot of bugs both from do-core and from plugins are fixed, the Docky interface also is enhanced, a couple of docklets are added as you can see in the screenshot above. You can now install the gnome-do-docklet package to get these docklets. (You need to enable them in the Plugin page of the Preferences dialog, and then activate them in the Appearance page — well, they only work for docky)

Here are some highlights I can think about among all the fixes/improvements:

Repository-less plugin system. The plugin installation is much simplified thanks to Alex’s non-repository fix. Now the plugin files will not be stored as copies in your home folder, which means in the future when the plugins package gets updated, the plugins you are using will be automatically the newest.
Docklets!. Jason has mentioned before it won’t be hard to write docklet because the framework is already there. So here we are with 5 docklets available: Battery Monitor, CPU Monitor, Switcher, Volume Control and Weather. At least 2 more are coming soon, namely the GMail and NetworkManager docklet.
Expanded keyboard shortcut options. You can now customize almost all major operations of Do with you own taste. For me, since I use Emacs a lot, I’d like to have the Previous/Next results configured as Ctrl-P/Ctrl-N and Browse into/Step out of item as Alt-F/Alt-B, so my right hand doesn’t need to leave the home row to reach the arrow keys.
More “browsable” items. You can browse into the “Home Folder” item and mounted disk item (if you are using the DiskMounter plugin) with “Right Arrow” key (the default key binding for Browse into a item) now. The ~ and ~user can be correctly expanded, so you can also simply open or browse your home folder, other user’s home folder or any path containing them.
Enhanced Copy/Paste. Copy/Paste is consistent now whether you are using Ctrl+C or the ‘Copy to Clipboard’ action. The text getting copied will depend on the type of the item you are copying. For example, if you are copying a URL item, you will always have the URL copied to the clipboard, no matter how the item’s title and description looks like.
Configuration Page for Docky. Docky has a simplified menu on the Do item on the dock, and most of the configuration options have been moved to the Appearance page of the Preferences dialog.
Dropbox Plugin. We have a new Dropbox plugin written by Stephen Elson. We all love Dropbox for its usefulness and convenience, with the plugin, you can share or synchronize your files even more easily.
Improved RTM Plugin. The RTM plugin should be stable enough for most people no matter if you have like 100 tasks in your account, and a lot of features are added, for details please read my other post.

There are of course many other fixes/improvements I can not remember well, please jump to the mailing list or release announcement for more information.

As mentioned in another post in the mailing list, we will have a minor release very soon (in 1—2 weeks) to address some bugs found out during the use of this new version. A few other improvements may also be included by then (like the GMail docklets :). Stay tuned!

Note: You need to enable the Do-Core PPA to get the new 0.8.2 packages. And currently only Karmic and Jaunty platform have the gnome-do and gnome-do-plugins packages ready, the gnome-do-docklets may need some more time to get in, as well as packages for other platform (intrepid/hardy, due to their relatively old mono version).

Disable gnome-screensaver while using mplayer

noreply@blogger.com (Peng) — Sat, 02 Jan 2010 04:09:23 PST

Just a quick post about an ignoring problem I had with Ubuntu 9.04 (Jaunty): I am a big fan of mplayer and it is the only player that can play 720p HD movie smoothly without having CPU running at top speed (2 GHz) on my 3.5 years old laptop (Thinkpad T43). However starting with 9.04, the screensaver keeps coming up while mplayer is playing — I don’t remember this uses to happen. I have stop-xscreensaver="yes" inside ~/.mplayer/config but this seems not doing the trick.

After checking the manual of mplayer, I managed to work this around by putting

heartbeat-cmd="gnome-screensaver-command -p"

into the config file. The heart beat command will run every 30 seconds, and gnome-screensaver-command -p will poke the screen saver daemon to let it know we are still up to something (not idle).

Note: maybe it is all because I’m using the latest svn version of mplayer packaged on a PPA — too lazy to test with the original version from Ubuntu’s repo for the time being, please leave a comment if you are using the latter and this doesn’t affect you, thanks.

Remember The Milk plugin for GNOME Do Updates

noreply@blogger.com (Peng) — Thu, 11 Jun 2009 08:01:12 PDT

After I finished my master thesis, I’ve been working on some changes to the RTM and Ping.FM plugin. With this post I’d like to give an simple update to the RTM plugin, by listing some of the new features that the new version will offer and a few bugs that has been/will be solved. This new version will (hopefully) be shipped with the up coming release of Do (0.8.2).

Changes behind the scene

Re-factored internal data structure. The data structure to store tasks/lists are much simplified which allows more features to be added relatively with less efforts.
Throttling Control. Added self-control inside RtmNet API to avoid server side throttling. Now we will send request to RTM server with interval no less than 1 second. Thanks to IronCow for the inspiration!
Improved synchronization with RTM server. Ensure synchronized content between Do universe (items indexed by Do) and your account in the cloud. If you modified any tasks elsewhere, the changes will be noticed by Do automatically. Obsolete items (deleted/completed) will not be left inside Do universe.

New features and improvements

Directly indexed tasks. Now the tasks are first class citizen in Do universe which means they are accessible directly by typing the name of a task.
New ways to navigator to tasks. There are 2 new item sources which means in addition to navigating to a task via the list it belongs to, you can also access tasks by their locations or tags.
Expandable task item. Each of the task can be expanded (by using “right arrow” key with default key bindings) to show some sub-items related to the task (if it has any). e.g. tags, location, estimated time.
Tags/Locations/Notes/Estimated Time support. You can easily add/remove tags, locations, notes and set estimated time now. They are also indexed and shown as sub-items of a task.
- For adding tags, both hand typing (divided by a comma) and selecting from a existing tag list are supported.
- For adding notes, you can separate the title and body of a task by either a “|” character or a new line.
- The location associated with a task can be open in Google maps according to its latitude/longitude information
List actions. 3 new actions are added to provide functionality to create, rename and delete a list (except the reserved ones by RTM).
4 meta lists. 4 “smart” list to offer easy access to tasks due today/tomorrow/in 1 week and overdue tasks.
Configurable overdue task notification interval. It was annoying before when you were seeing the notifications every 2 minutes once you had overdue tasks, so I add a configuration option in the preferences dialog to let you choose the interval between each notification, the default value is 15 minutes.

Bugs fixed

Bug #351564: RTM blocks startup, and crashes when internet is not available
Bug #324980: Remember the Milk not connecting with delayed network connection

Though I think it is ideal that the Universe Manager in Do core will be capable of handling plugin activation depending on the network status, I let RTM try re-connecting during universe update if it has not yet established a connection to RTM server.
Bug #314798: after RTM plugin install: Do crashes after first character entered and Bug #370279: RTM plugin does not show the list of tasks

These 2 bugs are actually connected — the latter is due to a temporary work around (which didn’t really fix the problem) to get rid of the crash in the former bug. The symptom is, when the tasks in an RTM account to be indexed are of large amount (40+), the XML received from RTM server is simply truncated at some random point, so you will either see Do crashes because the unfinished XML causes a parser exception (Bug #314798) or Do indexes no tasks after I only catch the exception which avoid the crash but can not help recovering the task list.

I am not able to fix this bug for quite while simply because I cannot reproduce it in my system so I didn’t know in what way the XML became invalid, and testing with other users may expose their privacy to me, I cannot complain if no one would like to send me the problematic XML. Fortunately I recently received great help from Arnaud and Knorcedger who have been having this issue and are kindly enough to share their private info with me only to help me debugging. I would like to thank them for their support without which I don’t know when I could figure out where is wrong with the code. So I tried several different way to track down the real reason of the issue, and eventually it turns out it was the slightly-mistyped request URL in the original RtmNet API this plugin uses that causes the big trouble.

About Synchronization

One thing you may notice which behaves not as the same as the old version is that any change you have made to your RTM data (tasks, lists, tags …) will not be seen synchronized immediately inside Do universe. Normally you need to wait 2 minutes (10 minutes if you are using laptop and on battery) before any changes to be reflected inside Do. This is actually a by-product of ensuring better synchronization, because modifying data out of Do’s update cycles (what we use to do) can potentially leave obsolete data permanently inside Do. I suppose most the users can wait that 2 minutes, but in case you just need to access an item you’ve just changed, you can force Do to do a universe update by open the Preferences dialog and close it, then after a second or two, you should see the changes.

Test

You can test this new version by either compiling the code yourself or downloading a pre-compiled DLL file. Please keep in mind this is still a beta software and may still have bugs. So please feel free to let me know by emailing or leaving comments here if there is any problem.

Compile from source

You can compile the source code pulled from this Launchpad branch. It is important to know you need to also have the latest Do compiled from the trunk code and installed. Please refer the wiki page on how to compile and install Do from source.
Pre-compiled Binary

To save you some time, there is a pre-compiled binary DLL file you can use. The download address is: http://dl.getdropbox.com/u/110544/do-plugins/edge/RTM.dll. It has been tested with both GNOME Do 0.8.1.3 and the latest bzr code.

To use it with Do 0.8.1.3, you need to make sure you clean the old DLL installed in you home folder, the safest steps to do that are:
1. Open the Preferences dialog and deactivate the Remember The Milk plugin.
2. Remove the folder “~/.local/share/gnome-do/plugins-0.8.1.3/addins/Do.RememberTheMilk.1.0/” and its content
3. Remove the file “~/.local/share/gnome-do/plugins-0.8.1.3/addin-db-001/addin-data/global/Do.RememberTheMilk,1.0.maddin”
4. Go to the folder “~/.local/share/gnome-do/plugins-0.8.1.3/addin-db-001/addin-dir-data/” and remove the file whose name contains “Do.RememberTheMilk.1.0”
5. Then you can copy the RTM.dll file into “~/.local/share/gnome-do/plugins-0.8.1.3/”, start Do, you should now have the 1.5 version of Remember The Milk in use.

Essential LaTeX packages for Producing Nice Looking Papers

noreply@blogger.com (Peng) — Thu, 21 May 2009 15:08:03 PDT

Finally I’ve finished my Master thesis and presentation. — although I was required to use a PPT template for my presentation thus I couldn’t use Beamer, I finished the whole thesis using LaTeX/Metapost, and this time I become completely a fan of MetaPost and learned again a little more about LaTeX, especially the convenience brought by several useful packages. Here I note them down together with some simple examples. In case you need to write a paper or thesis, they may help you a lot to produce a decent looking document.

graphicx

This is a very common package to include images into the document. And quite often, you may need to let the package look for image files in directories not the same as where the .tex file is stored. Therefore you need this small trick at the preamble part:

 \graphicspath{{metapost/}{gnuplot/}{figures/}}

Here I just let it look for images from 3 sub-directories, you can also use absolute path.

amssymb, amsmath, amsthm

These 3 packages are essential if what you plan to write about contains lots of mathematic equations, definitions etc. They offer features to align/position the equations nicely and also allow you to define you own theorem/theorem style.

% define new theorem style and new theorem
\newtheoremstyle{example}%
{}{}{}{\parindent}{\bfseries}{:}{.5em}{}%

\theoremstyle{example}
\newtheorem{ex}{Example}[chapter]

listings

If you like me need to include some source code snippet into the text, this package can help you format the code properly according to the programming language.

By default it doesn’t use a monospaced font, which I feel a bit weird, so I changed it globally at the preamble part

\lstset{language=C,basicstyle=\ttfamily,captionpos=b,tabsize=4,showspaces=false}

You can notice I also define the default lanuage as C so it will use special font style for key words in C.

subfig

Sometimes you need to have to graphs in one figure shown as (a) and (b), this package allows you to flexibly control the sub-figures including their captions, it also provide a command to let you refer to a specific sub-figure when you need to.

\begin{figure}
  \centering
  \subfloat[][Load]{\includegraphics[scale=1]{mt-load}}%
  \qquad
  \subfloat[][Load and Store]{\includegraphics[scale=1]{mt-load-store}}
  \caption{Multi-thread Data Load/Store (Data item size: 128 Byte)}
  \label{fig:mt-load}
\end{figure}

fancyref

If you would like to save the effort of typing in all the “chapter/section/page” text before you use the \ref command, and if you would like to make them fancier, e.g. section 4.2.3 on page 14 (text in bold are added automatically by the package), you can try this package out. It just needs you to prefix all you labels according to the type of environments they point at. For example, by default chap: for chapter, fig: for figure etc.

Moreover, you can to define new prefixes for the environments fancyref doesn’t know. In my case, it doesn’t cover the lstlisting environment and example theorem. So I have them defined as

\newcommand*{\fancyreflstlabelprefix}{lst}
\frefformat{\fancyrefdefaultformat}{\fancyreflstlabelprefix}{list\fancyrefdefaultspacing#1}
\Frefformat{\fancyrefdefaultformat}{\fancyreflstlabelprefix}{List\fancyrefdefaultspacing#1}
\newcommand*{\fancyrefexlabelprefix}{ex}
\frefformat{\fancyrefdefaultformat}{\fancyrefexlabelprefix}{example\fancyrefdefaultspacing#1}
\Frefformat{\fancyrefdefaultformat}{\fancyrefexlabelprefix}{Example\fancyrefdefaultspacing#1}

booktabs, longtable

These 2 packages will help you make better looking tables, the first will provide commands for different borders (top/middle/bottom) and the width of them are adjusted to make the table look more professional. longtable, as the name suggested, will help you fit long table across pages with optionally repeated header anf footer.

Besides these packages, I also practices this time to organize the whole document more effeciently by writing each chapter in a independent file and use the \input command of LaTeX to include them in the main (master) .tex file. This will let you better control the structure of the document and easily product partial document with selected chapters. Also the AUCTeX package for Emacs has support to such multi-file arrangement. It can write some meta information inside the slave tex files (files you include), then let you jump from a slave file directly to the master one, and you can also compile the whole document right inside the slave file. (C-c C-c).

RTM Plugin @ RTM

noreply@blogger.com (Peng) — Wed, 18 Mar 2009 05:35:34 PDT

It’s a great day today. It’s sunny (though still cold, but I have to appreciate the sunshine since I’m in Germany.), and I found out just after getting up this morning that Remember the Milk Plugin for GNOME Do is introduced at RTM’s official blog, together with the screencast. I am trilled.

I haven’t been able to work on GNOME Do/Plugins too much recently due to the fact it’s close to the deadline to submit my Master Thesis and another paper. I have planned some changes to RTM plugin, including new features suggested here and an approach to display the notes/tags/location etc. These things will probably be implemented slowly (most likely after next month). But luckily enough, Jonathan has joined the fun and started contributing some code.

Stay tuned, Do and RTM lovers!

GNOME Do 0.8.1

noreply@blogger.com (Peng) — Fri, 13 Mar 2009 19:16:39 PDT

GNOME Do had a breath-taking release last month with the fantastic Docky interface, and now one month later, we have a new minor release with a lot of small fixes — 0.8.1. There are a couple of visible and functional changes to docky and many bug fixes. Please step by Jason’s blog and the release note for details of this release.

I didn’t have too much time coding recently due to my thesis work and also a paper to submit. Nevertheless, I am completely sure Do will get better every day (sometimes even every hour :) !

Congrats!

Repairing Corrupt RAID 1 Partitions

noreply@blogger.com (Peng) — Fri, 13 Mar 2009 08:16:24 PDT

The lab computer I am using has a raid configuration consists of 2 500GB SATA hard disk. When I installed Fedora on the PC, I also setup it in a way that my /boot, / and swap partitions are all MD devices. I mentioned before, that this system has had a failure due to corrupt superblock. Yet I haven’t figured out the reason, the same situation happened again yesterday. I think I have to note the steps of repairing it down because I’ve already a bit confused yesterday as to how I did it the first time.

The failure is during booting. The normal procedure will be interrupt with error messages similar to this:

mdadm: WARNING /dev/sda6 and /dev/sdb6 appear to have very similar superblocks. If they are really different, please —zero the superblock on one If they are the same or overlap, please remove one from the DEVICE list in mdadm.conf.

And following that will be a “failed to mount /root fs” error.

First of all, this is a RAID 1 configuration with 3 MD devices: md0, md1 and md2.

md0 consists of sda6 and sdb6 and is mounted to /boot
md1 consists of sda7 and sdb7 and is mounted to /
md2 consists of sda8 and sdb8 and is used as swap

sda6, sdb6, sda7, sdb7 are all of type ext3.

Since it’s RAID 1, the content on both of the partitions associated with each MD device should be the same, and it seems the superblock appears to be different (“very similar”), so when the MD device try to assemble them, it fails. Therefore, without any activated MD devices, no surprise that the root filesystem can not mount. (I guess other two MD devices didn’t work either at that time.)

I booted to the rescue system provided by Fedora installation kernel. It can be reached from the installation media (CD, DVD) or GRUB if your /boot folder has the vmlinuz and initrd images needed for a hard disk installation. If it is CD/DVD, enter linux rescue when you start it, in the case of GRUB, the lines to start look like this: (you can enter it line-by-line after you press c)

root (hd0,5)
kernel vmlinuz-install rescue
initrd initrd-install.img
boot

Once in the command line interface after the rescue system is booted. You may or may not have the /dev/md* devices, but I guess that doesn’t matter. What matters is you should have the mdadm command and you know where is the original mdadm.conf file.

The first thing is to get the make mdadm.conf file accessible. So I mounted one of the root partitions (e.g. /dev/sdb7) to /mnt/sda7. At these time if you issue command like

mdadm -D /dev/md0 --config /mnt/sdb7/etc/mdadm.conf

you will be told the MD device is not active. But if you try to assemble it using

mdadm -A /dev/md0 --config /mnt/sdb7/etc/mdadm.conf

you will get the same warning message during booting process.

My trick here is, since MD knows how to synchronize two partitions if their contents are different and are supposed to be consistent, I can active an MD device with only one of the partition, so I won’t get the warning and at least the MD device will be up running, then I hot plug the other partition and rest of the work would leave to the MD system.

I don’t know if there is a one-liner for assembling MD device with selective partition, but I do know if the device is “busy”, it won’t be assembled. So I mount /dev/sdb6 and /dev/sdb8(using swapon /dev/sdb8) too and then try assembling all MD devices again. This time all MD devices is activated with only one of their partitions. Then we can unmount the intentionally occupied partitions, mount the /dev/md1 device (so we still have access to the mdadm.conf file, of course you can alternatively copy that file to the current system to avoid this mounting operation) and use the following command to add them to their respective MD devices.

mdadm /dev/md0 --add /dev/sdb6 --config /mnt/md1/etc/mdadm.conf
mdadm /dev/md1 --add /dev/sdb6 --config /mnt/md1/etc/mdadm.conf
mdadm /dev/md2 --add /dev/sdb6 --config /mnt/md1/etc/mdadm.conf

Now only one step is left: waiting. Depending on how large your partitions are, the re-synchronizing process could take hours. (My root partition is 90GB and it took around half an hour to finish the synchronizing.) You can check the progress by checking the content of file /proc/mdstat. When it’s done, reboot and Viola, problem solved.

Using mailer.py to send SVN Commit Notificaiton Email

noreply@blogger.com (Peng) — Thu, 12 Feb 2009 14:35:44 PST

Yesterday when I tried to find a way to get the SVN server send out an email whenever there is a commit, I first came across commit-email.pl via Google. But it turned out that script is deprecated and the newer/cooler version is mailer.py. However there is not so much information on how to use the latter although it is not so complicated, so here is a quick note.

To get the script, there is a package in the repo called subversion-tools, it will install a couple of scripts inside /usr/share/subversion/hook-scripts/ and one of them is mailer.py.

mailer.py needs an configuration file, and if not specified, it will search for a file called mailer.conf in your svn repo’s conf folder. You can find an example configuration file inside the same folder where the mailer.py script stays. I copied that example to /var/svn/repos/conf/ (you may want to change it to match your svn repo path) and changed the content to match the setting I prefer. There are plenty of comments inside the file so you will mostly figure out everything easily. A stripped version of my mailer.conf looks as following:

[general]
mail_command = /usr/sbin/sendmail
smtp_hostname = localhost

[defaults]
diff = /usr/bin/diff -u -L %(label_from)s -L %(label_to)s %(from)s %(to)s
commit_subject_prefix = [SVN-Commit]
propchange_subject_prefix =
lock_subject_prefix =
unlock_subject_prefix =
from_addr = admin@mydomain.com
to_addr = receiver1@mydomain.com receiver2@mydomain.com
reply_to =
generate_diffs = add copy modify
commit_url = https://trac.mydomain.com/changeset/%(rev)s
show_nonmatching_paths = yes

[maps]

When the configuration file is in place, the next thing needs to be done is enable the actual hook. You will find several script template inside the hooks folder of your svn repo. Rename the one called post-commit.tmpl to post-commit and make it executable. The content of it is very simple, just replace the last line with

/usr/share/subversion/hook-scripts/mailer/mailer.py commit "$REPOS" "$REV"

That’s it. Next time when some one commits some code, the post-commit hook will trigger the mailer.py script and all the addresses in the to_addr field of the configuration file will receive an notification email.

A quick follow-up to Do/Docky

noreply@blogger.com (Peng) — Fri, 30 Jan 2009 02:32:10 PST

If you just started using Do with Docky, maybe there are two or three small things you want to know:

Adjust the dock size and zoom ratio precisely.

This can be done using gconf-editor a.k.a “Configuration Editor”. Go to apps/gnome-do/Docky/Utiliteis/DockPreferences, on the right side, you can find IconSize and ZoomPercent. I like to have 48 for the former, which is the smallest size that allows summon mode to have 2 lines. And I use 1.5 for the latter cause default 2.0 feels just too huge to me ;)
If you have encountered this issue with Remember The Milk plugin I coded, there is already a quick fix but it is too late to get it included in the final release. Though you can find the DLL file with the fix here if you really need it: http://dl.getdropbox.com/u/110544/do-plugins/RTM.dll. Overwrite the file ~/.local/share/gnome-do/plugins-0.8.0/addins/Do.RememberTheMilk.1.0/RTM.dll with the new one.
Now that you have the dock, you may miss the “Genie” effect for minimizing windows like how windows are minimized in Mac OS X. Since “Genie” is protected by patent, Compiz decides to disable the option to set “max wave size” of its “Magic Lamp” effect to 0 so that you can not mimic the “Genie” effect with it. While I use to recompile the whole compiz package to get around this limitation, there is easier way to do this if you know how to search in Google. Just in case you need a HEX editor, Emacs’s hexl-mode can actually handle it pretty well.

Do 0.8: Rock out with your dock out

noreply@blogger.com (Peng) — Fri, 30 Jan 2009 02:32:29 PST

Today is a big day for all Do users and developers, cause 0.8 a.k.a “Rock Out With Your Dock Out (ROWYDO)” is finally released!

As some of you have already known from the alpha/beta testing, the biggest highlight of this release is this awesome new UI — “Docky”. Docky is another interface for Do, yet it introduces an entirely new way to use Do. It preserves all Do’s original functionalities and keyboard-based interaction philosophy while it provides a smooth dock with parabolic effect which introduces mouse-based interaction to Do and makes it very enjoyable to play with your most frequently used applications, directories etc. You can find more information about Docky here at this wiki page.

The new Do also has a lot of improvements over the previous version. Many bugs have been fixed and a new architecture has been applied, which make Do more stable, consume less memory and have the potential to be cross-platform in the future.

There are certainly also improvements to plugins and many more new plugins become available. Twitter plugin has been renamed to “Microblogging”, with the new ability to post to Identi.ca; Remember the Milk and Ping.FM plugins are also included as communicty plugins in this release :). You probably would be surprised while looking through the list of all these useful plugins — almost 70 of them :).

If you want to find more more about this release, please check out David, Jason, Alex, Cimi, Kalle or Michael's blogs. To start using the new Do, add Do’s PPA to your software package repositories, and update/install “gnome-do” and “gnome-do-plugins” . If you don't use Ubuntu, check out the download page for more specific information for your distribution. You can also compile it yourself from the source code according to the installation guide. If you encounter any problem while using Do, please report it via the bug track at Launchpad (while if it’s a plugin bug, you should file it here instead), or discuss it with other Do user and Do developers at the IRC channel (irc.freenode.net, #gnome-do).

For all these awesomeness, I want to thank everyone who has contributed to and supported this project, especially our core developers! David, Jason, Alex, you guys really make Do one of the best apps in my system and an essential program to my every day use! I’m also very happy to contribute some code to Do, it just feels so right to do something useful to an app that brings so much convenience to my life.

Manually Make an External Disk Bootable Using GRUB

noreply@blogger.com (Peng) — Wed, 28 Jan 2009 06:18:43 PST

Yesterday I was facing a corrupt Linux system which needs a re-installation. I didn’t have the right to modify the boot order stored in the BIOS and the only thing boots before internal hard drive is the USB device. I had an external hard disk handy but I was surprised that the USB start-up disk creation tool in Ubuntu didn’t recognize my disk — does it only support flash memory devices? I then decided to manually make the USB hard disk bootable and boot it into Ubuntu’s hard disk installation kernel. Since it took me some effort to get to the preferable result from Google, I put the steps here in case anyone including myself needs it in the future.

Prerequisite: A running Linux system to format the external disk, transfer files and setup GRUB. I use my Ubuntu laptop here.

Create a partition on the external disk

The size should be enough to contain an Ubuntu alternative installation images plus GRUB files and kernel images, 800 MB would be a safe guess. (If you want to install any other distribution e.g. Fedora, the size should be adjusted to be capable of storing the CD/DVD image size of that distribution). The format I used was ext3, I think any file system that GRUB supports and the installation kernel can search the CD/DVD image from should be OK. To create the partition, I used GParted, while you can use any of the partition tool that fits your taste. After creating the partition, you should know the device id of it (e.g. /dev/sdb1) and mount it to you system if it is not automatically mounted.
Setup the directory structure and copy necessary files
- First copy the alternative installation image onto the newly created partition.
- Then create a boot folder containing a grub folder. You can use command mkdir -p /boot/grub to do it in one pass. If there is any problem performing write operation in the partition, change the owner of the mount point of this partition to yourself. (sudo chown -R user:user /media/<mount point of the partition>)
- Now you can copy all GRUB files to /boot/grub from /usr/lib/grub/i386-pc/ of your running Ubuntu system. You can also create a menu.lst file here which makes it automatically boot the installation kernel files, but it is not necessary as you can simply issue the 4 lines of commands after booted into the GRUB console. (see the last paragraph of this post)
- Last files to copy are the kernel images, normally vmlinuz and initrd.gz. They can be downloaded from Ubuntu’s repo at http://archive.ubuntu.com/ubuntu/dists/intrepid/main/installer-i386/current/images/hd-media/ and should be put into /boot/. The release and the platform string should be changed according to the target system.
Setup GRUB
- Enter the GRUB console as root.
```
$ sudo grub
  
```
- Change root to your new partition. (e.g. /dev/sdb1)
```
grub> root (hd1,1)
  
```
- Setup GRUB. This will look for the essential files in the partition and write proper data into the MBR of your external disk to make it bootable.
```
grub> setup (hd1)
  
```
- You should see some output of a successful installation and now it’s time to quit from the GRUB console and start installing a new system using this external hard disk.
```
grub> quit
  
```

When the target PC starts with the external disk plugged, it will boot into the GRUB console, you can then use root, kernel, initrd and boot command to find and boot the kernel image files. Following is how I used the commands in details. Please be aware of the possibility that the hard disk order is not the same as on you other system. You might need some “heuristic” to get to the right partition. (TAB rocks!)

root (hd0,1) <ENTER>
kernel /boot/vmlinuz <ENTER>
initrd /boot/initrd.gz <ENTER>
boot

Simple Remote Control with Dropbox

noreply@blogger.com (Peng) — Sun, 11 Jan 2009 09:05:03 PST

Dropbox is a fantastic application for unobstructive synchronization of files between multiple computers running different operating systems. Everything happens seamlessly behind the scene. The more I use it the more I feel thankful to the creators and devs. Today I found out a new use of Dropbox — a simple remote control tool. All you need is Dropbox and some shell scripts.

The Scenario

Why I would have come up with such an idea? The story is: I have a PC at home which I would like to access from the lab in the institute. It is reachable only if it’s connected to the VPN network in the campus. However, the VPN connection is sometimes not very stable and could die with no reason, not to say the server will automatically terminate a connection from outside of the university every 4 hours.

Therefore I really want to find a way to remotely issue commands on my home PC (which is unreachable), let it connect to the VPN network and report the IP address to me. With Dropbox, its very easy to do.

The Solution

I create a cron job on the home PC, which checks a text file (command.txt) inside my Dropbox folder every minute, when its not empty, execute the content of the file (and clear the file). On the lab PC, I can simply put the command I want to execute into the same file — since its synchronized seconds after I made the modification, it will soon be executed at home. And for reporting IP address, I wrote a wrapper script which runs on home PC to check the VPN status after connecting and redirect the IP address information into another text file (ip.txt) inside Dropbox folder. So when I am in the lab, I put the VPN wrapper script’s name inside the command.txt, maximum a minute later, I check the ip.txt. Now I can ssh to my home PC and do what ever I want.

The Script

I put up together a script which does both the adding command and the checking-then-running command job. I call it “dbrun” which is short for “Dropbox Run”. It can be download here (right-click and save).

Installation & Usage:

Make sure Dropbox daemon is up and running in both systems.
Put dbrun in both the controlling and controlled systems. I prefer the directory ~/.local/bin.
Make it executable if it’s not. chmod +x dbrun
Create a cron job to run dbrun in a short interval (e.g. 1 min) in the controlled system. I do this by creating a file crontab inside ~/.local/etc and then run crontab ~/.local/etc/crontab. The content of the file is:
```
PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin:/usr/local/bin:/home/pdeng/.local/bin
*/1 *   *   *   *   dbrun
```
You may have noticed since I put dbrun in ~/.local/bin, I include this directory in the $PATH environment variable. (Actually other scripts like my VPN wrapper is also there, so I have to do this).
Now to issue a command, run dbrun 'new command' in the controlling system, you will notice the Dropbox systray icon start animating to indicate the synchronization of the modified command.txt file. The “new command” will be executed soon in the controlled system.

The default location I use to store the command.txt file in the script is ~/Dropbox/command.txt. You can change it to whatever you like by opening the script and changing the value of cmdfile(around line 11).

Security Concern

It is possible to modify the script to let it only run filtered safe commands you selected yourself. But as long as you are not stupid enough to mark the command.txt as “shared” in your Dropbox and you don’t run the script as root, I don’t see (for now) too much danger. Maybe I am too naïve so please let me know in the comment if there is any potential security issue that I overlooked. After all, I only let it help getting my home PC reachable and SSH will be used to finish all other things afterward.

Update: I just did a quick check on Dropbox's wiki (didn't know about this wiki before) and there is already a similar solution for remote control. The advantages of that one is a) it has smaller granularity as it runs in a big loop and check the file every 10 seconds. b) it redirect the output into another file which can be very useful sometimes. Maybe next I should do some search in Google before writing on my own, hehe ...

Integrate Remember The Milk's Tasks into Evolution

noreply@blogger.com (Peng) — Thu, 07 May 2009 12:44:42 PDT

Today’s Lifehacker has an article about how to integrate Google’s Apps into Evolution, which reminds me I always want to integrate Remember The Milk’s task list into evolution and eventually let it show in the nice looking drop down window of the clock applet on GNOME’s panel.

It should be easy because with the latest (at least, don’t know about previous version) Evolution you can create new task list of the type “On The Web”, for which you will need a webcal URL which you can find at Remember The Milk’s Info page (Using the Settings link in the upper right corner of your RTM webpage, and you will see the Info tab).

Well if you just fill in the URL and your username, you probably will get an error about some sort of authorization problem. Here is the workaround: simply add username & password combination into the address string as seen in the picture below.

After the task list is created, you will be asked for the password again (you may want to choose remember it as well), and then you should see all the tasks in you RTM account, incomplete or completed, be retrieved from the server. And meanwhile in the drop down window of the clock applet, all incomplete task should appear.

Quite like how Evolution handled Google Calendar before, the RTM task list is, for the time being, read-only, i.e. you can only see them but not add/remove/mark as complete etc. However, for me, this is exactly where RTM plugin of GNOME Do should play its role, the integration just gives me a better way to keep an eye on the tasks.

How to get high-resolution Netbeans icon on Linux

noreply@blogger.com (Peng) — Fri, 21 Nov 2008 09:40:28 PST

I always like to have nice looking icons for my application launchers. Especially when using GNOME Do, launchers with icon smaller than 128x128 pixels looks always like shit.

So choosing a good icon theme is very important for me. I am currently using the “Gnome Brave” theme from Gnome-colors package, it provides a wide-range of scalable icons in SVG format, meaning these icons can fit into any size required.

However there are always some apps that the theme hasn’t cover, like eclipse, Netbeans etc. In this case, I have to look for good quality icons for them, which can be very hard sometimes.

I actually have been trying to find a high-res icon for my Netbeans but haven’t had any luck. But today when I searched again and came across some pictures of how Netbeans launcher looks on Mac’s dock, I saw a very large, slick icon. Then I looked into Netbeans folder and noticed there was a file with extension .icns. It turned out this is one of the icon file formats used by Apple on Mac. And luckily enough, on Linux there is an utility, icns2png which extracts the PNG files contained inside .icns file.

If you use Ubuntu/Debian, this tool is right in the repository so just install the icnsutils package. Then by issuing the following command in a terminal, you can extract the 128x128-pixel 32-bit PNG file from the Netbeans.icns file:

icns2png -x -s 128 -d 32 netbeans.icns

BTW: if you also need an icon for Eclipse, I found one with Tango style in SVG format here: http://www.gnome-look.org/content/show.php?content=45585

And if you are curious what the app is in the screenshots, it is a new interface in development for GNOME Do, a dock implementation which also provides basic Do functionalities. It is so far the best dock I’ve ever used on Linux.

Update: I just updated the Gnome-colors theme and they include an tangoish Eclipse icon. So if you are using this theme, you can save some effort, but please notice, the one used by Gnome-colors is another version which doesn't have the 3 horizontal stripes in design.

Updates to Ping.FM and Remember The Milk plugin

noreply@blogger.com (Peng) — Wed, 07 Jan 2009 07:19:37 PST

Due to the recent changes to GNOME Do’s plugin API, I updated the code for Remember The Milk and Ping.FM plugin, mostly by using IEnumerable to replace the arrays.

The new code has been pushed to their launchpad address respectively, but they won’t be compatible with the current release of GNOME Do, ~~and not even the code in trunk can use this version. You may need them only if you are using the code from “future” branch.~~ You need this version only if your Do is compiled from the source code of current development version.

There are the compiled binaries from the latest code:

Old versions (which should be used with all released versions of Do, recommended version is 0.6.0+ except future)

Ping.FM.dll (rev 266)
RTM.dll (rev 271)

When you decide to checkout the code and compile them yourself, you should use the arguements -r revno:271 for RTM and -r revno:266 for Ping.FM if your Do installation is not of development version.

Update: David has merged the code of both RTM and Ping.FM plugin into community plugin, so you now you can also check out the code at lp:do-plugins/community.

My Emacs Color Theme

noreply@blogger.com (Peng) — Sun, 02 Nov 2008 09:10:16 PST

This is my emacs color theme, adjust based on the “Sunburst” theme for TextMate which is created by Soryu.

The el file can be found here: http://p3n9.kilu.de/color-theme-sunburst.el

Remember The Milk plugin for GNOME Do (video)

noreply@blogger.com (Peng) — Sat, 03 Jan 2009 07:25:04 PST

Just finished it, more information about it is coming soon.

Source code can be grabbed from here: http://code.launchpad.net/~do-plugins/do-plugins/community.

Compiled binary (usage: download the .dll file and put in your ~/.local/share/gnome-do/plugins-0.x.x folder and restart Do)

For GNOME Do version 0.6.*: http://p3n9.kilu.de/do-plugins/old/RTM.dll
For GNOME Do compiled from bzr trunk code (using the new plugin API): http://dl.getdropbox.com/u/110544/do-plugins/RTM.dll

Do's Upcoming Feature Demo

noreply@blogger.com (Peng) — Thu, 09 Oct 2008 15:26:32 PDT

Ha, My first Youtube video

No more < br / >

noreply@blogger.com (Peng) — Thu, 09 Oct 2008 07:03:06 PDT

Just realized I can turn off the “converting return character to <br />” option at blogger’s setup page. It was a disaster for me if there is no such a thing because I like to write the post in Markdown format in Emacs and convert it to HTML then post. To make the content easy to read, the lines are normall truncated into a limited length. For the previous post, I have to connect all the lines into one line before posting, which sounds rediculous.

From now on, no more stupid BR’s, haha!

Test Post from Emacs

noreply@blogger.com (Peng) — Thu, 09 Oct 2008 05:02:03 PDT

I’m now using G-Client, an Emacs client for several Google service to try to post a test entry. It allows you to directly edit the xml which will be sent out. This looks tricky, but on the other hand, you are able to add labels to the post. This makes the whole thing more useful.

Well, let’s first see if it works before talking too much shit.

Latest Looks of My Intrepid (Sreenshots)

noreply@blogger.com (Peng) — Thu, 09 Oct 2008 02:55:19 PDT

Thanks to the fabulous Dust GTK theme and Gnome Brave icon theme, plus the nice looking new wallpaper from Gnome 2.24, the desktop looks really decent now. This color scheme gets along very well with the upcoming Gnome Do HUD interface.

New Bluetooth Tools Arrived In Intrepid

noreply@blogger.com (Peng) — Thu, 07 May 2009 12:51:45 PDT

It’s great to have this update befor the final release, cause it is a lot easier to use than the previous old version in the repo. No more messing around with configuration files, all operation can be done via GUI. Kudos goes to bluez devs!

Do 0.6.1Released, SCIM Support in Development

noreply@blogger.com (Peng) — Tue, 07 Oct 2008 21:07:53 PDT

There is a minor release of GNOME Do lately, 0.6.1 - Before the Storm. It addresses severl bug fixes, especially the most annoying and infamous clip board bug introduced with 0.6.0, which may consume very high cpu resouces and freeze the system. This release also improves on dealing with special characters like “<”. A new icon also has been used.

If you are still using 0.6.0, very likely you’ve already been suffering from the clipboard bug, now it is time to upgrade. If you are with older version, this new release should be good and stable enough for you to switch to.

To install the new version, you can either grab the source code from https://launchpad.net/do/0.6/0.6.1 and compile it yourself, or add the do-core PPA into your sources.list and install via apt-get or Synaptic.

Meanwhile, Jason (DBO) is doing extraordinary works to bring new features to the development branch which will become the next Do release 0.7. Yesterday he added a exciting feature which allows users to use SCIM to input in Do. This feature must be quite important to CJK users (or any user that needs SCIM to type words on daily basis).

Like 2 month ago, I was think about this issue that Do may not be so useful to CJK users as to users who type without an IM since for CJK users normally there must be a decent amount of items that Do indexes are in Chinese/Japanese/Korean and without IM suport, these items are almost unreachable (well, you still could navigate to them using arrows maybe, but … you don’t want to do that too often if you want to be efficient). At that time I was even planned to solve this problem and did give it some (stupid) thoughts. But I didn’t imagine it could be such a straight forward approach like this: using the Gtk.IMContext class.

So now you can use SCIM fairly well with Do, though you may want to turn off the “Embed Preedit String into window” option cause Do’s interface actually cannot display those inline preedit string for now.

With the also newly added “paste support” feature, Do’s Text Mode is much easier to use. If you want to test it out, you can grab DBO’s branch using bzr:

bzr co lp:~jassmith/do/do-uiwork/

With this code, you can also find other amazing things he has been working on, like the new animated HUD theme (engine), the one you could see from the screenshot above.

GNOME Do是一个类似苹果Mac OS中QuickSliver或Windows下Launchy的软件，可以避免不必要的鼠标操作，利用键盘的便捷性快速的启动应用程序，打开文件或文件夹，并通过几十种不同的可选插件完成诸如添加事件至Google日历，上传图片至ImageShack，打开Firefox书签，发送信息至Twitter等任务，是你系统的“遥控器“，追求效率的同学之必备软件。现在Gnome的开发分支已经加入了对SCIM输入法的支持，使用中文的同学可以更精确的使用Do，新的代码可以通过上面提到的 BZR命令获取。

Do got shadows!

noreply@blogger.com (Peng) — Mon, 06 Oct 2008 05:43:39 PDT

Cimi, the core developer behind the fantastic murrine GTK/Cairo theme engine, the one that drives a lot of beautiful GTK themes nowadays, branched Do's code and added a new look to the UI, with some very nice looking shadows. Although I have no idea when Do 0.7.0 will be released, but what for sure is by then Do will definitely have an impressive UI, thanks to the work by DBO & Cimi.

Gnome 2.24 is released, Get the Wallpapers

noreply@blogger.com (Peng) — Mon, 06 Oct 2008 05:45:03 PDT

Finally after 6 months of hard work by developers, Gnome 2.24 is here today, with lots of new features and improvements. This time the wallpapers also become more beautiful than before thanks to the contest held 5 months ago.

For Ubuntu 8.10 Intrepid Users, to get those sexy new wallpaper, simple install the gnome-backgrounds package from synaptics or from command line by sudo apt-get install gnome-backgrounds. If you are staying with hardy or older version but still want to enjoy the new look, grab it from gnome’s ftp: http://ftp.gnome.org/pub/GNOME/sources/gnome-backgrounds/2.24/gnome-backgrounds-2.24.0.tar.bz2