Definition of fopen function under VS2017
_Check_return_ _CRT_INSECURE_DEPRECATE(fopen_s)
_ACRTIMP FILE* __cdecl fopen(
_In_z_ char const* _FileName,
_In_z_ char const* _Mode
);
_ACRTIMP:
#define _ACRTIMP __declspec(dllimport) The macro definition declares the external function
FILE.
The return value of this function is the FILE structure pointer
In_z char const* _FileName
file path name whose type is char const*
The open mode type of In_z char const _Mode file is char const*
mode:
| r | Read only mode is on |
|---|---|
| w | Write only mode on |
| a | Open for writing, create if not, add data to the end of the file |
| r+ | Read and write open |
| w+ | Open for reading and writing, empty if it exists |
| a+ | Read and write open. Remove the EOF mark first, and then reply to the EOF mark after the operation is complete. |
Modes can be combined operation
I don’t understand other macro definitions for the time being, and I will add them later if I understand them. Or the great god tells me directly in the comments below.