Sami Wagiaalla's Blog

int main(){
  int *a;
  int b[3] = {1,2,3};
  a = b;

  int *c[3] = {a, b, 0};
  int **d = c;
  return 0;
}

While debugging the above code if you do:

(gdb) print b
$4 = {1, 2, 3}

that works.

(gdb) print a
$5 = (int *) 0x7fffffffe0f0

that works too, but in order to print a as an array you must do:

(gdb) print (int []) *a
$7 = {1}

and when you specify the size it gets better:

(gdb) print (int [3]) *a
$8 = {1, 2, 3}

The same goes for c and d:

(gdb) p c
$9 = {0x7fffffffe0f0, 0x7fffffffe0f0, 0x0}
(gdb) p (int*[3]) *d
$10 = {0x7fffffffe0f0, 0x7fffffffe0f0, 0x0}
(gdb) 

And finally a very recently discovered short hand thanks to Jan Kratochvil:

(gdb) p *a@3
$11 = {1, 2, 3}
(gdb) p *d@3
$12 = {0x7fffffffe0f0, 0x7fffffffe0f0, 0x0}

I only discovered this awesome podcast recently:

http://surprisinglyfree.com/

I highly recommend it.

For a quick log of what I have on my branch/repo which I have not pushed upstream I do this:

git log --pretty=oneline --branches --not --remotes=origin

A tip I got from Dodji:

git-new-workdir

creates a new working directory that shares the repository of your original clone. If like me you like to create a new direcotry for each branch you are working on this is a much faster way to do it. It also has the added bonus of being awair of you other directories so you can share commits whithought having to git remote add

In my Fedora 13 installation. This is currently located at

/var/lib/mock/fedora-14-x86_64/root/usr/share/doc/git-1.7.2/contrib/workdir/git-new-workdir

I am a big fan the of the Thunderbird search bar. It has definitely helped my productivity. The star is awesome.

I have recently discovered jessyink. Jessyink is an inkscape extention which allows you do create presentation slides in inkscape, save them as svg, and display them using firefox.

I think that when you start your presentation in inkspace instead of OpenOffice Impress, it puts your mind in a more graphical mode. This mindset helps you create slides which are more graphical and less verbose/text heavy/bullet-pointy.

I found this excellent tutorial which helped me get started with jessyink.

One thing I would like to add that tutorial:

Creating Views

You can add zooming, panning and rotation effects to you slides. (Use with caution. These are addictive).
To do this you have to first create view ports using rectangles. Using the inkscape rectangle tool create a rectangle. Position and size it around the part of the slide that you want to focus on. Once you have done that go to Extensions -> Jessyink -> view… .

On that screen select an order. This determines when in the order of events the transition to this view happens. Duration will determine how long it should take to transition from the old view to this view. Click apply and you are done.

Now if you want the view port to rotate, simply select the rectangle you have created for the view, click on it again and rotate it. You can experiment with it to know how exactly that will work.

You can checkout this cheesy example if you want. Use mouse click or arrow keys to navigate through the presentation.

While back a reader of my blog, Jonner, requested a C++ feature in GDB; smart pointers. I am glad to say that this work is very close to complete, pending approval to commit upstream.

Supporting smart pointers boils down to supporting the overloading of operator-> which was a bit tricky.
Take this example:

class A{
  public:
    int foo() {return 11;}
}

template <typename T> class SmartPointer{
  T *p;
  public:
    SmartPointer(T *pointer){
      p = pointer;
    }

  T *operator->(){
    return p;
  }
};

int main(){
  A a;
  SmartPointer<A> sp(&a);
  sp->foo();
}

In the code above when we are calling

sp->foo()

(sp->)->foo()