#define callback __stdcall # Define Winapi __stdcall # Define Winapiv __cdecl # define apientry winapi # define apiprivate __stdcall # define pascal __stdcall
Calling Convention: Determines the order of the stack and out of the stack when the function parameter is transmitted, and the argument is bounced by the caller or by the caller, and the compiler is used to identify the modification of the function name. The function call is agreed to have a variety of simplicity: 1. __ stdcall calls agreement is equivalent to the PASCAL call convention used in the 16-bit dynamic library. In the 32-bit VC 5.0, the PASCAL call convention is no longer supported (in fact it has been defined as __stdcall. In addition to __pascal, __ fortran and __syscall are not supported), replaced by __stdcall call agreement. The two are substantially consistent, that is, the function's parameters pass the right left through the stack through the stack, the called function is returned to the memory stack of the transfer parameters, but the different part of the function name (about the modified part of the function name) The detailed description will be described later. _Stdcall is the default call mode of the Pascal program. It is usually used in the Win32 API. The function uses the stack of right to left, and the stack is cleared when you exit. The VC compiles the function before adding a downline prefix in front of the function name, plus the number of bytes of "@" and parameters after the function name. 2, c call convention (ie, using __cdecl keyword description) Press the parameter from right to left, and populates the argument by the caller. For the memory stack of the transfer parameters, it is maintained by the caller (for this, the function that implements variable parameters can only use the call convention). In addition, there is also different in terms of function name modification. _CDECL is the default call mode of the C and C programs. Each function that calls it contains the code that clears the stack, so the resulting executable size is larger than the call _stdcall function. The function uses the stack of right to left. VC compiles the function and adds a downline prefix in front of the function name. It is an MFC default call convention. 3, __ fastCall call agreement is "person", such as its name, its main feature is fast, because it passes the parameter through the register (actually, it uses ECX and EDX to transfer the first two double words (DWORD) or smaller The parameters, the remaining parameters are still transmitted to the left stack, the called function is returned to the internal memory stack of the transfer parameters before returning), and in terms of the function name modification, it is different from the top. _FastCall mode functions use register pass parameters, and VC compiles the function after the "@" prefix in front of the function name, add the number of bytes of "@" and parameters after the function name. 4. ThisCall is only applied to the "C " member function. The THIS pointer is stored in the CX register, the parameter is left from right to left. Thiscall is not a keyword, so it cannot be designated by the programmer. 5, Naked Call When using 1-4 call conventions, if necessary, the compiler generates code to save the ESI, EDI, EBX, EBP registers, generate code recovery of these registers when entering the function. Naked Call does not produce such a code. Naked Call is not a type modifier, so you must use the _declspec. Keywords __stdcall, __ cdecl, and __fastcall can be selected before the functionality of the function you want to output, or you can choose the SETTING ... / C / C / Code Generation item of the compilation environment. When the keyword before the output function is not in the compilation environment, the keyword before the output function is added directly before the output function is valid. The corresponding command line parameters are / Gz, / GD, and / GR, respectively. The default state is / gd, ie __cdecl.
