The GlideSystem server-side API is not constructed using the new keyword, but is available to all server-side scripts via the variable gs. This API allows us to get various kinds of useful information about the system, the user's session, the current date/time, or other bits of useful info. It also allows you to interact with the user, by displaying informational or error messages.

addErrorMessage() and addInfoMessage()

The addErrorMessage() method will display a red error message at the top of the user's browser window on the next page they load after the server-side script that calls this method runs. This same functionality can also be achieved from a client-script, using the g_form API (g_form.addErrorMessage()).

addInfoMessage() ...

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