waiting for help about to understanding the wap/wsp/wtp/wtls source codes

.I have read the protocol specifications doc such as wap-wtp-wtls 
        downloaded from the wapforum,and understand how it works,but when i am 
        reading the source codes of the wap/wsp/wtp/wtls,i'm very much 
        puzzled,because they were defined in a very mysterious or magical way: los of 
        struct/enum/union with ( #define/"include...") in them,and also i can not 
        understand how the definitions in the *def works,the styles of them 
        looks like the overloading functions of C++,but i have never seen such 
        styles in C before------.....Can someone teach me how to understand theirs Working principle??? 
        thanks a 
        lot...
                                                                                       ZH   from  China



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