XmClipboardStartCopy(3Xm)

NAME
XmClipboardStartCopy — a clipboard function that sets up a storage and data structure.

SYNOPSIS
#include <Xm/Xm.h>
#include <Xm/CutPaste.h>

int XmClipboardStartCopy (display, window, clip_label, timestamp, widget, callback, item_id)
    Display    * display;
    Window    window;
    XmString    clip_label;
    Time    timestamp;
    Widget    widget;
    VoidProc    callback;
    long    * item_id;

DESCRIPTION
XmClipboardStartCopy sets up storage and data structures to receive clipboard data. An application calls this function during a cut or copy operation. The data item that these structures receive then becomes the next data item in the clipboard.

Copying a large piece of data to the clipboard can take time. It is possible that, once copied, no application will ever request that data. The Motif Toolkit provides a mechanism so that an application does not need to actually pass data to the clipboard until the data has been requested by some application.

Instead, the application passes format and length information in XmClipboardCopy to the clipboard functions, along with a widget ID and a callback function address that is passed in XmClipboardStartCopy. The widget ID is needed for communications between the clipboard functions in the application that owns the data and the clipboard functions in the application that requests the data.

The callback functions are responsible for copying the actual data to the clipboard via XmClipboardCopyByName. The callback function is also called if the data item is removed from the clipboard, and the actual data is therefore no longer needed.

display
    Specifies a pointer to the Display structure that was returned in a previous call to XOpenDisplay or XtDisplay.

window
    Specifies a widget's window ID that relates the application window to the clipboard. The widget's window ID can be obtained by using XtWindow. The same application instance should pass the same window ID to each of the clipboard functions that it calls.

clip_label
    Specifies the label to be associated with the data item. This argument is used to identify the data item, for example, in a clipboard viewer. An example of a label is the name of the application that places the data in the clipboard.

timestamp
    Specifies the time of the event that triggered the copy.

widget
    Specifies the ID of the widget that will receive messages requesting data previously passed by name. This argument must be present in order to pass data by name. Any valid widget ID in your application can be used for this purpose and all the message handling is taken care of by the cut and paste functions.

callback
    Specifies the address of the callback function that is called when the clipboard needs data that was originally passed by name. This is also the callback to receive the delete message for items that were originally passed by name. This argument must be present in order to pass data by name.

item_id
    Specifies the number assigned to this data item. The application uses this number in calls to XmClipboardCopy, XmClipboardEndCopy, and XmClipboardCancelCopy.

For more information on passing data by name, see XmClipboardCopy(3Xm) and XmClipboardCopyByName(3Xm).

The widget and callback arguments must be present in order to pass data by name. The callback format is as follows:

function name
	Widget	widget;
	int	* data_id;
	int	* private;
	int	* reason;

widget
    Specifies the ID of the widget passed to this function.

data_id
    Specifies the identifying number returned by XmClipboardCopy, which identifies the pass-by-name data.

private
    Specifies the private information passed to XmClipboardCopy.

reason
    Specifies the reason, which is either XmCR_CLIPBOARD_DATA_DELETE or XmCR_CLIPBOARD_DATA_REQUEST.

RETURN VALUE

ClipboardSuccess
    The function is successful.

ClipboardLocked
    The function failed because the clipboard was locked by another application. The application can continue to call the function again with the same parameters until the lock goes away. This gives the application the opportunity to ask if the user wants to keep trying or to give up on the operation.

RELATED INFORMATION
XmClipboardCancelCopy(3Xm), XmClipboardCopy(3Xm), XmClipboardCopyByName(3Xm), XmClipboardEndCopy(3Xm), XmClipboardEndRetrieve(3Xm), XmClipboardInquireCount(3Xm), XmClipboardInquireFormat(3Xm), XmClipboardInquireLength(3Xm), XmClipboardInquirePendingItems(3Xm), XmClipboardLock(3Xm), XmClipboardRegisterFormat(3Xm), XmClipboardRetrieve(3Xm), XmClipboardStartRetrieve(3Xm), XmClipboardUndoCopy(3Xm), XmClipboardUnlock(3Xm), and XmClipboardWithdrawFormat(3Xm).