The implementation of a new compressing mode is a very interesting area .. maybe I'll try something
(but I assume not as soon as appreciated)
The big problem with the SDK licence is that you cannot release any project without having one.
If you do, the cryption formula code has to be released, too, a matter that makes it absolutely senseless. The hackers only have to copy the code and crypt your string in the mainfile to get the password.
Means, anyone who wants to develop a new cryption method or even just wants to use the simple .zip one has to have the SDK licence.
Sure, if there would be anyone who has purchased it already and develops a new compressing UI and so on, the 'normal' users without can use that. But then it will cost money as well, because the developer has to earn the money for his licence ^^
[EDIT]
To all trying the posted code:
if you use version 6.4 and above, "add_buffer" requires a size parameter. "add_buffer(char* name,void* buffer,long size)"
You just have to add a little piece of code..
Code:
add_buffer(filename_withoutpath, buf, size_buf);
