Windows Pipe & Process

win_pipe.c

int run_external(const char* command)
{
    int rval = 1;

    SECURITY_ATTRIBUTES attr = {
        .nLength = sizeof(attr),
        .lpSecurityDescriptor = NULL,
        .bInheritHandle = TRUE
    };

    HANDLE read_pipe, write_pipe;
    if (CreatePipe(&read_pipe, &write_pipe, &attr, 0) == 0)
    {
        _E("pipe error\n");
        goto e0;
    }

    STARTUPINFO si = {
        .cb = sizeof(si),
        .dwFlags = STARTF_USESTDHANDLES,
        .hStdOutput = write_pipe,
        .hStdError = write_pipe
    };

    PROCESS_INFORMATION pi = {0};

    BOOL success = CreateProcess(
        NULL,
        (char*) command,
        NULL,
        NULL,
        TRUE,
        DETACHED_PROCESS,
        NULL,
        NULL,
        &si,
        &pi
    );

    CloseHandle(write_pipe);

    if (!success)
    {
        _E("can't create process for:\n  %s\n", command);
        goto e1;
    }

    char buffer[1024];

    bool done = false;
    while (!done)
    {
        DWORD bytes_read = 0;
        done = !ReadFile(read_pipe, buffer, sizeof(buffer), &bytes_read, NULL);

        if (bytes_read > 0)
        {
            /* TODO */
            fprintf(stdout, "%s", buffer);
            fflush(stdout);
        }
    }

    DWORD exit_code = 0;
    GetExitCodeProcess(pi.hProcess, &exit_code);

    rval = exit_code;
    _I("%s returned with error code %d\n", command, rval);

    CloseHandle(pi.hProcess);
    CloseHandle(pi.hThread);
e1:
    CloseHandle(read_pipe);
    //CloseHandle(write_pipe);
e0:
    return rval;
}