XAddConnectionWatch(3X11)XLIB FUNCTIONS XAddConnectionWatch(3X11)



NAME
     XAddConnectionWatch, XRemoveConnectionWatch, XProcessInter-
     nalConnection, XInternalConnectionNumbers - handle Xlib
     internal connections

SYNTAX
     typedef void (*XConnectionWatchProc)(display, client_data,
     fd, opening, watch_data)
           Display *display;
           XPointer client_data;
           int fd;
           Bool opening;
           XPointer *watch_data;

     Status XAddConnectionWatch(display, procedure, client_data)
           Display *display;
           XWatchProc procedure;
           XPointer client_data;

     Status XRemoveConnectionWatch(display, procedure,
     client_data)
           Display *display;
           XWatchProc procedure;
           XPointer client_data;

     void XProcessInternalConnection(display, fd)
           Display *display;
           int fd;

     void XProcessInternalConnection(display, fd)
           Display *display;
           int fd;

     Status XInternalConnectionNumbers(display, fd_return,
     count_return)
           Display *display;
           int **fd_return;
           int *count_return;

ARGUMENTS
     client_data
               Specifies the additional client data.

     count_return
               Returns the number of file descriptors.

     display   Specifies the connection to the X server.

     fd        Specifies the file descriptor.

     fd_return Returns the file descriptors.




X Version 11         Last change: Release 6                     1






XAddConnectionWatch(3X11)XLIB FUNCTIONS XAddConnectionWatch(3X11)



     procedure Specifies the procedure to be called.

DESCRIPTION
     The XAddConnectionWatch function registers a procedure to be
     called each time Xlib opens or closes an internal connection
     for the specified display.  The procedure is passed the
     display, the specified client_data, the file descriptor for
     the connection, a Boolean indicating whether the connection
     is being opened or closed, and a pointer to a location for
     private watch data.  If opening is True, the procedure can
     store a pointer to private data in the location pointed to
     by watch_data; when the procedure is later called for this
     same connection and opening is False, the location pointed
     to by watch_data will hold this same private data pointer.

     This function can be called at any time after a display is
     opened.  If internal connections already exist, the
     registered procedure will immediately be called for each of
     them, before XAddConnectionWatch returns.  XAddConnec-
     tionWatch returns a nonzero status if the procedure is suc-
     cessfully registered; otherwise, it returns zero.

     The registered procedure should not call any Xlib functions.
     If the procedure directly or indirectly causes the state of
     internal connections or watch procedures to change, the
     result is not defined.  If Xlib has been initialized for
     threads, the procedure is called with the display locked and
     the result of a call by the procedure to any Xlib function
     that locks the display is not defined unless the executing
     thread has externally locked the display using XLockDisplay.

     The XRemoveConnectionWatch function removes a previously
     registered connection watch procedure.  The client_data must
     match the client_data used when the procedure was initially
     registered.


     The XProcessInternalConnection function processes input
     available on an internal connection.  This function should
     be called for an internal connection only after an operating
     system facility (for example, select or poll) has indicated
     that input is available; otherwise, the effect is not
     defined.






X Version 11         Last change: Release 6                     2






XAddConnectionWatch(3X11)XLIB FUNCTIONS XAddConnectionWatch(3X11)



     The XInternalConnectionNumbers function returns a list of
     the file descriptors for all internal connections currently
     open for the specified display.  When the allocated list is
     no longer needed, free it by using XFree.  This functions
     returns a nonzero status if the list is successfully allo-
     cated; otherwise, it returns zero.

SEE ALSO
     Xlib - C Language X Interface














































X Version 11         Last change: Release 6                     3