I searched the web and Google told me I need to specify the full path (no ~ or $HOME etc.) of the database file and the web server needs the write permission to the file. Sure, I actually had done both before the exception occurred.

Having being pissed for a while, I finally figured out what was wrong here: The web server needs the write permission to not only the database file, but also the containing directory of that file.

Yea, just simple like that.

Requirement:

• Python >= 2.5

How to use it:

1. Download yahoo.weather.py.
2. Edit the file, fill in required parameters (read CONFIGURATION first).
3. Add ${execi 3600 python the_path_to/yahoo_weahter.py} to your .conkyrc.

If you have problem to compile Broadcom 802.11 Linux STA driver (version 5.10.27.6) on Kernel 2.6.27 and get error message like the following:

/home/ye/downloads/bcm4328/hybrid_wl/src/wl/sys/wl_iw.c: In function ‘wl_iw_get_scan’:
/home/ye/downloads/bcm4328/hybrid_wl/src/wl/sys/wl_iw.c:934: warning: passing argument 1 of ‘iwe_stream_add_event’ from incompatible pointer type
/home/ye/downloads/bcm4328/hybrid_wl/src/wl/sys/wl_iw.c:934: warning: passing argument 3 of ‘iwe_stream_add_event’ from incompatible pointer type
/home/ye/downloads/bcm4328/hybrid_wl/src/wl/sys/wl_iw.c:934: warning: passing argument 4 of ‘iwe_stream_add_event’ makes pointer from integer without a cast
/home/ye/downloads/bcm4328/hybrid_wl/src/wl/sys/wl_iw.c:934: error: too few arguments to function ‘iwe_stream_add_event’
/home/ye/downloads/bcm4328/hybrid_wl/src/wl/sys/wl_iw.c:939: warning: passing argument 1 of ‘iwe_stream_add_point’ from incompatible pointer type
/home/ye/downloads/bcm4328/hybrid_wl/src/wl/sys/wl_iw.c:939: warning: passing argument 3 of ‘iwe_stream_add_point’ from incompatible pointer type
/home/ye/downloads/bcm4328/hybrid_wl/src/wl/sys/wl_iw.c:939: warning: passing argument 4 of ‘iwe_stream_add_point’ from incompatible pointer type
/home/ye/downloads/bcm4328/hybrid_wl/src/wl/sys/wl_iw.c:939: error: too few arguments to function ‘iwe_stream_add_point’
...

Then you need to apply the patch: hybrid_wl-5.10.27.6_patch-2.6.27

How to apply the patch:

1. Download the STA driver and the patch.
2. Extract the STA driver and switch to the root of source tree (where Makefile is located).
3. patch -p1 -E < path_to_patch/hybrid_wl_5.10.27.6_patch-2.6.27

1. Run the command line program (cmd/powershell) as Administrator (right-click -> Run as Administrator), then issue the following command:
2. msiexec /i path_to_the_msi\python-2.6.msi

That’s it!

via

x = 5
y = 3

temp = x
x = y
y = temp

We need a temporary variable as a container to hold a value first then do the swap.

What if in some situation you can’t use the extra variable? How would you do it?

Well, let’s forget computer programming but pick up some little math we learned in elementary school:

x = 5
y = 3

x = x - y (=2)
y = x + y (=5)
x = y - x (=3)

Here we go!

Update 2008-10-6: please don’t use the y410_sound script from this article since I don’t own a Y410 anymore, so I couldn’t test and maintain the script. Instead, please follow the solutions given in the comments. They seem to work pretty well.

Update 2008-4-3: This script will only make speaker work, but not headphone. As Sam mentioned, there is another easy way to get sound work without installing anything: Suspend your machine and resume. The drawback is you have to do it every time after you (re)boot.

Well, this is another post about Ubuntu 8.04!

As I mentioned before, Lenovo Y410 laptop’s sound card wouldn’t work out of box on Ubuntu 8.04, which is very disappointing for Y410 owners like me.

Fortunately, we can solve this problem in the same way as on Ubuntu 7.10 and the most intuitive solution I could find on Internet is “Getting Sound to work on your Ubuntu 7.10 installation on Lenovo Y410 Series laptop”. Thanks the author, Ambuj Varshney, for the good job!

The solution is straightforward, but it’s kind of verbose there are too many steps to perform, kind of; so I wrote a bash script to do the job. You can download the script from my box.

After you downloaded this script (y410_sound-20080427.sh), run it as follow:

chmod +x y410_sound-20080427.sh
sudo ./y410_sound-20080427.sh

This script may take a long time to finish since it will download all the required packages and compile the driver, so please be patient.

After it’s done, reboot your Y410 and then you should be able to enjoy your music!

Note: I only tested this script on my Lenovo Y410. If you have any problem while applying this script, please leave comments.

Merry Christmas, everyone!

Here is my solution:

class Foo
{
public:
    Foo(const Foo& f) {}
    static Foo getAnInstance()
    {
        return Foo();
    }
private:
    Foo() {}
};

Explanation:

To prevent users from creating objects on heap, I basically can’t give them any public constructors (ctor); therefore, I need to write at least one ctor myself and make it private since if I fail to do so, the compiler will generate a public default ctor for me and that is exactly what I don’t want. Then the user can only use the static member function getAnInstance to get an object to use.

Analysis:

In fact, my solution contradicts the explanation because I actually have a public ctor — the copy ctor. The copy ctor makes the following usage work:

Foo f0 = Foo::getAnInstance();

But because there is a copy ctor, after the user get his/her first object, he/she can do the following:

Foo* f1 = new Foo(f0);

This is saying that my solution can only guarantee the first object is on stack and it can’t go further.

So, my solution fails to solve the question.

p.s. I haven’t really seen the point of the interview question, but it’s interesting to think about ;)

Update:

The correct solution is to overload the new operator and make it private. Credit to DANIWEB

When you are going though a document in VIM, you find a word and you want to go to the next same word in the document, you just need to put the cursor on the word and press * (SHIFT + 8).

What if you want to the previous one? Answer: # (SHIFT + 3).