Listening a file descriptor
[MiniGUI-Processes 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 303 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.