Debugging

The application is presumably working, so there is nothing to debug, really.

Still, let's use this starter project to learn the basics of debugging.

Place a breakpoint on the s=sock.getdata(sock.txfree) line. To do so, double click on the empty border to the left of this line.

A small red circle will appear there. That's your breakpoint.

Breakpoints can also be "toggled" (added/removed) by pressing [F9].

Press [F5] if you haven't yet started the execution.

Send something from I/O NINJA. The execution will BREAK at your breakpoint.

Now select Debug > Add to Watch List and add the variable s to the watch.

S is a string, in this application all received TCP data passes through it.

At first the variable is empty — this is because the "yellow line" (the execution pointer) hasn't been executed yet.

• Press [F8] to execute a single line of code. The yellow line will move, and the Watch pane will show you the new value of s. It will contain the string you've sent from NINJA.
• Press [F5] to resume the execution.