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<concept id="GUID-CABA0B4D-11E4-5659-B949-C4277FB63804" xml:lang="en"><title>Notifier</title><shortdesc>A notifier is a simple service that allows either a single line

message (an infoprint) or a simple dialog box to be displayed on the hardware's

display device. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>It is used for sending (debug) trace messages to the screen and putting

up debug dialog boxes. It can be used in any environment, including the text

shell used for development of engine or low level type code. Because it doesn't

require Uikon it is invaluable for developers who need to work without GUI

dependencies. </p>

<p>The dialog box consists of two lines of text and two buttons. The buttons

each display a single text character and the user is expected to key in one

of these characters. </p>

<p>The notifier is a server, managed by the Kernel. The client side creates

a session through an <codeph>RNotifier</codeph> handle. </p>

<p> <note/> If a plug-in notifier DLL fails to load successfully, the

OS will not start. Notifiers are critical system resources which must not

fail to load correctly. </p>