Method open

source/matplot/util/popen.cpp:11–94

#include <io.h>

int common_pipe::open(const std::string& cmd, char mode)
{
    if (opened())
        close(); // prevent resource leak
    HANDLE hChildStdinRd, hChildStdinWr, hStdin, hStdout;
    SECURITY_ATTRIBUTES saAttr{};
    // Set up security attributes for inheritable handles
    saAttr.nLength = sizeof(SECURITY_ATTRIBUTES);
    saAttr.bInheritHandle = TRUE;
    saAttr.lpSecurityDescriptor = NULL;

    // Create a pipe for the child process's input
    if (!CreatePipe(&hChildStdinRd, &hChildStdinWr, &saAttr, 0))
        return report(GetLastError(), "CreatePipe");

    // Ensure the write handle to the pipe is not inherited by child
    // processes
    if (!SetHandleInformation(hChildStdinWr, HANDLE_FLAG_INHERIT, 0)) {
        auto err = GetLastError();
        CloseHandle(hChildStdinRd);
        return report(err, "SetHandleInformation(hChildStdinWr)");
    }

    // Create a pipe for the child process's output
    if (!CreatePipe(&hStdin, &hStdout, &saAttr, 0)) {
        auto err = GetLastError();
        CloseHandle(hChildStdinRd);
        CloseHandle(hChildStdinWr);
        return report(err, "CreatePipe");
    }

    // Ensure the read handle to the output pipe is not inherited by child
    // processes
    if (!SetHandleInformation(hStdout, HANDLE_FLAG_INHERIT, 0)) {
        auto err = GetLastError();
        CloseHandle(hChildStdinRd);
        CloseHandle(hChildStdinWr);
        CloseHandle(hStdin);
        return report(err, "SetHandleInformation(hStdout)");
    }

    // Configure STARTUPINFO structure for the new process
    STARTUPINFO si{};
    ZeroMemory(&si, sizeof(STARTUPINFO));
    si.cb = sizeof(STARTUPINFO);
    si.hStdError = hStdout;
    si.hStdOutput = hStdout;
    si.hStdInput = hChildStdinRd;
    si.dwFlags |= STARTF_USESTDHANDLES;
    PROCESS_INFORMATION pi;

    // Create the child process, while hiding the window
    if (!CreateProcess(NULL, const_cast<char *>(cmd.c_str()), NULL, NULL, TRUE,
                       CREATE_NO_WINDOW, NULL, NULL, &si, &pi)) {
        auto err = GetLastError();
        CloseHandle(hChildStdinRd);
        CloseHandle(hChildStdinWr);
        CloseHandle(hStdin);