See Assembly code generated for your source code

To study internals, we often need to refer assembly code.

Method to generate assembly code
1. Take “Project settings” by Alt+F7
2. Go to “C/C++” tab.
3. Select “Listing Files” from Category combo box.
4. Select “Assembly with source Code” form Listing file type combo box.
5. Recompile the project.
6. Take the debug or release directory, you can see asm files

This can be done in another way, Just add /FAs to the “Project Options” edit box in the “C/C++” tab.

Difference between ::PostMessage and ::SendMessage APIs

The difference between these two APIs is that the way they return control to the calling application. With SendMessage, the control doesn’t return to the calling application until the window process the message. However, PostMessage returns the control immediately after the message push to the windows message queue regardless whether the sent message has been processed or not.

Windows API reference

Windows API reference Windows API reference

What is the difference between UNICODE and _UNICODE

The purpose of the both preprocessor macros are same.

UNICODE is used by windows headers and _UNICODE is used by C-Runtime/MFC headers.