I want to hook some APIs. I has some questions when reading the article on codeguru website
http://www.codeguru.com/Cpp/W-P/dll...ticle.php/c127/

The sample in that article is to hook DirectDrawCreate function in DDRAW.dll, and change it with his own function in his own dll. I am just wondering why he set a global WH_CBT hook but with a callback function doing nothing (just do CallNextHookEx).

When I made some mouse hook or keyborad hook, I always did my work in the callback function, so I am confused that why we changed when do API hooking.

Thanks in advance!