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	DisplayAlert -- Create the display of an alert message.

	Response = DisplayAlert( AlertNumber, String, Height )
	D0			 D0           A0      D1

	BOOL DisplayAlert( ULONG, UBYTE *, UWORD );

	Creates an alert display with the specified message.

	If the system can recover from this alert, it's a RECOVERY_ALERT and
	this routine waits until the user presses one of the mouse buttons,
	after which the display is restored to its original state and a
	BOOL value is returned by this routine to specify whether or not
	the user pressed the LEFT mouse button.

	If the system cannot recover from this alert, it's a DEADEND_ALERT
	and this routine returns immediately upon creating the alert display.
	The return value is FALSE.

	NOTE: Starting with V33, if Intuition can't get enough
	memory for a RECOVERY_ALERT, the value FALSE will be returned.

	AlertNumber is a LONG value, historically related to the value
	sent to the Alert() routine.  But the only bits that are pertinent to
	this routine are the ALERT_TYPE bit(s).  These bits must be set to
	either RECOVERY_ALERT for alerts from which the system may safely
	recover, or DEADEND_ALERT for those fatal alerts.  These states are
	described in the paragraph above.   There is a third type of
	alert, the DAISY_ALERT, which is used only by the Exec.

	The string argument points to an AlertMessage string.  The AlertMessage
	string is comprised of one or more substrings, each of which is
	composed of the following components:
           - first, a 16-bit x-coordinate and an 8-bit y-coordinate,
             describing where on the alert display you want this string
             to appear.  The y-coordinate describes the offset to the
             baseline of the text.
           - then, the bytes of the string itself, which must be
             null-terminated (end with a byte of zero)
           - lastly, the continuation byte, which specifies whether or
             not there's another substring following this one.  If the
             continuation byte is non-zero, there IS another substring
             to be processed in this alert message.  If the continuation
             byte is zero, this is the last substring in the message.

	The last argument, Height, describes how many video lines tall you
	want the alert display to be.

	New for V36: Alerts are always rendered in Topaz 8 (80 column font),
	regardless of the system default font.  Also, RECOVERY_ALERTs are
	displayed in amber, while DEADEND_ALERTs are still red.  Alerts
	no longer push down the application screens to be displayed.  Rather,
	they appear alone in a black display.

	Also new for V36: Alerts block each other out, and input
	during an alert is deprived of the rest of the system.  Internal
	input buffers still cause alert clicks to be processed by
	applications sometimes.

	AlertNumber = the number of this alert message.  The only pertinent
	    bits of this number are the ALERT_TYPE bit(s).  The rest of the
           number is ignored by this routine.
	String = pointer to the alert message string, as described above
	Height = minimum display lines required for your message

	A BOOL value of TRUE or FALSE.  If this is a DEADEND_ALERT, FALSE
	is always the return value.  If this is a RECOVERY_ALERT. The return
	value will be TRUE if the user presses the left mouse button in
	response to your message, and FALSE if the user presses the right hand
	button is response to your text, or if the alert could not
	be posted.

	If the system is worse off than you think, the level of your alert
	may become DEADEND_ALERT without you ever knowing about it.  This
	will NOT happen due simply to low memory.  Rather, the alert
	display will be skipped, and FALSE will be returned.

	The left and right button clicks satisfying the alerts are
	unfortunately passed to	the normal applications, because of
	some internal system input buffering.


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