C language provides an interface does not allow the use of structure
since the use of the structure, may result in some data structure is not initialized, internal function processing to cause difficulties, can not distinguish whether the parameters are valid
C language conventions memory allocation
memory who apply and who is released, do not allow cross-release function, you need to have a cross-function and has the problem, you need to copy the memory
because if you do not apply for release, and the release prior to release on the error , will lead to memory leaks