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A programming puzzle

I'd like to share a programming puzzle that I've encountered recently. The requirement was interesting and I was thinking over it. Finally, I got a way to deal with these non-conventional requirements.
The requirement is something like below:

1. I need a program, which will launch another program from the command line (I mean Windows command line). I know this is not a big deal. But this requirement has two parts, which forced me to think:

1a. Once the user double clicks on the software, then a command prompt will launch and execute another program say notepad, and the command prompt will not return until the program launched (notepad) is closed by the user.

1b. If the user launches the program from an already open command prompt, then the prompt will not open another command prompt but launch another program (in this case notepad) and will not return until the launched program/process is closed.

This is a relationship of parent-child. The parent is looking after the child until the child's process has finished its execution.

This puzzle has a second part:
2. I also need the same program which launches Notepad through the command prompt will launch Notepad without launching the command prompt.
This is the whole story of the puzzle. The target platform is Windows.

The solution:

1. If you need a sample program, just write to me at "".
2. Else, follow the following step, to solve problem 1(both 1a and 1b):
   a. Create a win32 program
   b. Which should have a main and WinMain
   c. main () should have the logic to spawn a new process (in this case notepad). 
   d. Wait until the spawned process is in signaled state. 
   e. Compile the program with "Subsystem:Console".
3. To solve problem 2, call main from WinMain and compile the program in "Subsystem: Windows".

Image of the software follows:

1. Launch through the command prompt:

2. Launch by double-click, (Command launcher mode is on):

Happy programming...


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