How the process communicates between processes in Windows

An indirect way, you can use a "share name" to request a block of shared memory for reading and writing:

HANDLE　GetShare(char * &ShareP,int size,char *ShareName)
{
//ShareP申请的内存块地址，size字节数，ShareName共享名
HANDLE fh=CreateFileMapping((HANDLE)-1,0,PAGE_READWRITE,0,Size,ShareName);
ShareP=(char *)MapViewOfFile(fh,FILE_MAP_ALL_ACCESS,0,0,0);
if(GetLastError()!=ERROR_ALREADY_EXISTS)
　 ZeroMemory(ShareP,size);　// 共享区初始化
return(fh);
}
char * ShareP=NULL;
void　test()　// 申请一块128个字节的字符数组
　 {
　 HANDLE fh=GetShare(ShareP,128,"ShareForMyProg");
　 for (int i=0;i<128;i++)
　　 ShareP[i]=i;
　 CloseHandle(fh);
　 }

If you have multiple programs or the same program running multiple times, you can also use this method to enter the variable communication; Several of your processes can use this approach to communicate data to each other.