Listening a file descriptor
[MiniGUI-Lite specific functions]

Defines

• #define MAX_NR_LISTEN_FD   5

  The max number of listen fd which user can use.
  

Functions

• MG_EXPORT BOOL GUIAPI RegisterListenFD (int fd, int type, HWND hwnd, void *context)

  Registers a listening file descriptor to MiniGUI-Lite.
  

• MG_EXPORT BOOL GUIAPI UnregisterListenFD (int fd)

  Unregisters a being listened file descriptor.
  

---

Detailed Description

Register/Unregister a listen fd to MiniGUI.

When you need to listen a file descriptor, you can use select(2) system call. In MiniGUI, you can also register it to MiniGUI to be a listened fd, and when there is a read/write/except event on the registered fd , MiniGUI will sent a notification message to the registered window.

Example:

    ...

    /* Register to listen the read event of the master pty. */
    RegisterListenFD (pConInfo->masterPty, POLLIN, hMainWnd, 0);

    /* Enter the message loop. */
    while (!pConInfo->terminate && GetMessage (&Msg, hMainWnd)) {
        DispatchMessage (&Msg);
    }
    /* Unregister the listening fd. */
    UnregisterListenFD (pConInfo->masterPty);

    ...

/* The window procedure. */
static int VCOnGUIMainWinProc (HWND hWnd, int message, WPARAM wParam, LPARAM lParam)
{
    PCONINFO pConInfo;

    pConInfo = (PCONINFO)GetWindowAdditionalData (hWnd);
    switch (message) {

         ...

        /* MSG_FDEVENT sent by MiniGUI indicates that you should to read the data. */
        case MSG_FDEVENT:
            ReadMasterPty (pConInfo);
        break;

        ...
    }

    /* Calling default window procedure. */
    if (pConInfo->DefWinProc)
        return (*pConInfo->DefWinProc)(hWnd, message, wParam, lParam);
    else
        return DefaultMainWinProc (hWnd, message, wParam, lParam);
}

---

Define Documentation

#define MAX_NR_LISTEN_FD   5

The max number of listen fd which user can use. Definition at line 305 of file minigui.h.

---

Function Documentation

BOOL GUIAPI RegisterListenFD (  int  fd, int  type, HWND  hwnd, void *  context )

Registers a listening file descriptor to MiniGUI-Lite. This function registers the file desciptor fd to MiniGUI-Lite for listening. When there is a read/write/except event on this fd, MiniGUI will post a MSG_FDEVENT message with wParam being equal to MAKELONG (fd, type), and the lParam being set to context to the target window hwnd. Parameters: fd  The file descriptor to be listened. type  The type of the event to be listened, can be POLLIN, POLLOUT, or POLLERR. hwnd  The handle to the window will receive MSG_FDEVENT message. context  The value will be passed to the window as lParam of MSG_FDEVENT message. Returns: TRUE if all OK, and FALSE on error. Note: Only available on MiniGUI-Lite. See also: UnregisterListenFD, System messages

BOOL GUIAPI UnregisterListenFD (  int  fd  )

Unregisters a being listened file descriptor. This function unregisters the being listened file descriptor fd. Parameters: fd  The file descriptor to be unregistered, should be a being listened file descriptor. Returns: TRUE if all OK, and FALSE on error. Note: Only available on MiniGUI-Lite. See also: RegisterListenFD

---