I want to capture PuTTY's STDIN and STDOUT pipes. So I open putty.exe via CreateProcess with passing created pipes but I can't read anything from pipes. My code works when I run a bat file.
How can I accomplish this?
Thanks
//This code is from MSDN and I edited it a little #include <QCoreApplication> #include <windows.h> #include <tchar.h> #include <stdio.h> #include <strsafe.h> #pragma comment(lib, "user32.lib") #define BUFSIZE 4096 HANDLE g_hChildStd_IN_Rd = NULL; HANDLE g_hChildStd_IN_Wr = NULL; HANDLE g_hChildStd_OUT_Rd = NULL; HANDLE g_hChildStd_OUT_Wr = NULL; HANDLE g_hInputFile = NULL; void CreateChildProcess(void); void WriteToPipe(void); void ReadFromPipe(void); void ErrorExit(PTSTR); int main(int argc, char *argv[]) { SECURITY_ATTRIBUTES saAttr; // Set the bInheritHandle flag so pipe handles are inherited. saAttr.nLength = sizeof(SECURITY_ATTRIBUTES); saAttr.bInheritHandle = TRUE; saAttr.lpSecurityDescriptor = NULL; // Create a pipe for the child process's STDOUT. if ( ! CreatePipe(&g_hChildStd_OUT_Rd, &g_hChildStd_OUT_Wr, &saAttr, 0) ) ErrorExit((PTSTR)TEXT("StdoutRd CreatePipe")); // Ensure the read handle to the pipe for STDOUT is not inherited. if ( ! SetHandleInformation(g_hChildStd_OUT_Rd, HANDLE_FLAG_INHERIT, 0) ) ErrorExit((PTSTR)TEXT("Stdout SetHandleInformation")); // Create a pipe for the child process's STDIN. if (! CreatePipe(&g_hChildStd_IN_Rd, &g_hChildStd_IN_Wr, &saAttr, 0)) ErrorExit((PTSTR)TEXT("Stdin CreatePipe")); // Ensure the write handle to the pipe for STDIN is not inherited. if ( ! SetHandleInformation(g_hChildStd_IN_Wr, HANDLE_FLAG_INHERIT, 0) ) ErrorExit((PTSTR)TEXT("Stdin SetHandleInformation")); // Create the child process: putty CreateChildProcess(); // read from pipe and printf incoming data ReadFromPipe(); } // Read output from the child process's pipe for STDOUT // and write to the parent process's pipe for STDOUT. // Stop when there is no more data. void ReadFromPipe(void) { DWORD dwRead, dwWritten; CHAR chBuf[BUFSIZE]; BOOL bSuccess = FALSE; HANDLE hParentStdOut = GetStdHandle(STD_OUTPUT_HANDLE); for (;;) { bSuccess = ReadFile( g_hChildStd_OUT_Rd, chBuf, BUFSIZE, &dwRead, NULL); if( ! bSuccess || dwRead == 0 ) break; printf("received hex:\n"); for (int i = 0; i < dwRead; i++) { printf("%02X", chBuf[i]); } printf("\nactual string: %s\n",chBuf); } } void CreateChildProcess() // Create a child process that uses the previously created pipes for STDIN and STDOUT. { PROCESS_INFORMATION piProcInfo; STARTUPINFO siStartInfo; BOOL bSuccess = FALSE; // Set up members of the PROCESS_INFORMATION structure. ZeroMemory( &piProcInfo, sizeof(PROCESS_INFORMATION) ); // Set up members of the STARTUPINFO structure. // This structure specifies the STDIN and STDOUT handles for redirection. ZeroMemory( &siStartInfo, sizeof(STARTUPINFO) ); siStartInfo.cb = sizeof(STARTUPINFO); siStartInfo.hStdError = g_hChildStd_OUT_Wr; siStartInfo.hStdOutput = g_hChildStd_OUT_Wr; siStartInfo.hStdInput = g_hChildStd_IN_Rd; siStartInfo.dwFlags |= STARTF_USESTDHANDLES; // Create the child process. bSuccess = CreateProcess(L"E:\\putty.exe", NULL, // command line NULL, // process security attributes NULL, // primary thread security attributes TRUE, // handles are inherited 0, // creation flags NULL, // use parent's environment NULL, // use parent's current directory &siStartInfo, // STARTUPINFO pointer &piProcInfo); // receives PROCESS_INFORMATION // If an error occurs, exit the application. if ( ! bSuccess ) ErrorExit((PTSTR)TEXT("CreateProcess")); else { // Close handles to the child process and its primary thread. // Some applications might keep these handles to monitor the status // of the child process, for example. CloseHandle(piProcInfo.hProcess); CloseHandle(piProcInfo.hThread); } } // Format a readable error message, display a message box, // and exit from the application. void ErrorExit(PTSTR lpszFunction) { LPVOID lpMsgBuf; LPVOID lpDisplayBuf; DWORD dw = GetLastError(); FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, dw, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPTSTR) &lpMsgBuf, 0, NULL ); lpDisplayBuf = (LPVOID)LocalAlloc(LMEM_ZEROINIT, (lstrlen((LPCTSTR)lpMsgBuf)+lstrlen((LPCTSTR)lpszFunction)+40)*sizeof(TCHAR)); StringCchPrintf((LPTSTR)lpDisplayBuf, LocalSize(lpDisplayBuf) / sizeof(TCHAR), TEXT("%s failed with error %d: %s"), lpszFunction, dw, lpMsgBuf); MessageBox(NULL, (LPCTSTR)lpDisplayBuf, TEXT("Error"), MB_OK); LocalFree(lpMsgBuf); LocalFree(lpDisplayBuf); ExitProcess(1); }