XAddConnectionWatch, XRemoveConnectionWatch, XProcessInternalConnection,
XInternalConnectionNumbers - handle Xlib internal connections
typedef void (*XConnectionWatchProc)(Display *display,
XPointer client_data, int fd, Bool opening, XPointer *
Status XAddConnectionWatch(Display *display, XWatchProc
procedure, XPointer client_data);
Status XRemoveConnectionWatch(Display *display,
XWatchProc procedure, XPointer client_data);
void XProcessInternalConnection(Display *display, int
Status XInternalConnectionNumbers(Display *display, int
** fd_return, int *count_return);
- Specifies the additional client data.
- Returns the number of file descriptors.
- Specifies the connection to the X server.
- Specifies the file descriptor.
- Returns the file descriptors.
- Specifies the procedure to be called.
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 a nonzero status if the procedure is
successfully 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
function removes a previously registered
connection watch procedure. The client_data must match the client_data used
when the procedure was initially registered.
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
) has indicated that input is available; otherwise, the effect is
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
. This functions returns a nonzero status if the list is
successfully allocated; otherwise, it returns zero.
Xlib - C Language X Interface