通过匿名管道在进程间双向通信

Posted 2022-12-13 syd_programming

由于匿名管道只能是单向的，因此要建立双向通信必须建立2个管道。

父程序代码：

int main() //定义四个句炳保留两个管道的信息 HANDLE hReadPipe1, hWritePipe1, hReadPipe2, hWritePipe2; SECURITY_ATTRIBUTES sat; STARTUPINFO startupinfo; PROCESS_INFORMATION pinfo; BYTE buffer[1024]; DWORD byteRead, byteWrite; string rString; string m_Host= "Client.exe"; sat.nLength=sizeof(SECURITY_ATTRIBUTES); sat.bInheritHandle=true; sat.lpSecurityDescriptor=NULL; //创建管道，它用来做子进程的输出 if(!CreatePipe(&hReadPipe1, &hWritePipe1, &sat, NULL)) cout<<("Create Pipe Error!")<<endl; return 1; //创建管道，它用来做子进程的输入 if(!CreatePipe(&hReadPipe2, &hWritePipe2, &sat, NULL)) cout<<"Create Pipe Error!"<<endl; return 1; startupinfo.cb=sizeof(STARTUPINFO); //用GetStartupInfo获得当前进程的参数，否则STARTUPINFO参数太多，会让人抓狂 GetStartupInfo(&startupinfo); startupinfo.hStdInput = hReadPipe2; startupinfo.hStdError=hWritePipe1; startupinfo.hStdOutput=hWritePipe1; //要有STARTF_USESTDHANDLES，否则hStdInput, hStdOutput, hStdError无效 startupinfo.dwFlags=STARTF_USESHOWWINDOW | STARTF_USESTDHANDLES; startupinfo.wShowWindow=SW_HIDE; if(!CreateProcess(NULL, (char*)m_Host.c_str(), NULL, NULL, TRUE, NULL, NULL, NULL, &startupinfo, &pinfo)) cout<<("create process error!")<<endl; return 1; RtlZeroMemory(buffer,1024); //进程的输出重定向到hWritePipe1，所以从hReadPipe1读取 // 在从管道中读取到数据前父进程将发生阻塞 if (ReadFile(hReadPipe1,buffer,1023,&byteRead,NULL)) cout<<buffer; string csWrite = "ping www.sina.com.cn/r/n"; //进程的输入重定向到hReadPipe2，所以从hWritePipe2写入 // 向管道中写数据不会发生阻塞，此循环会一直执行下去。 while (WriteFile(hWritePipe2, (LPCVOID)csWrite.c_str(), csWrite.length() + 1, &byteWrite, NULL)) cout << "write " << byteWrite << endl; CloseHandle(hReadPipe1); CloseHandle(hReadPipe2); CloseHandle(hWritePipe1); CloseHandle(hWritePipe2); return 0;   

 

子进程代码：

 int main(int argc, char* argv[]) hRead = GetStdHandle(STD_INPUT_HANDLE); hWrite = GetStdHandle(STD_OUTPUT_HANDLE); char s[] = "Hello, I am child process/n"; DWORD dwWrite; if (!WriteFile(hWrite, s, strlen(s) + 1, &dwWrite, NULL)) out << "Write to pipe failed!" << endl; return -1; char buf[100]; DWORD dwRead; if(!ReadFile(hRead, buf, 100, &dwRead, NULL)) out << "Read from pipe failed!" << endl; return -1;