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Source ensure_x_server(+Display, +Depth)
Ensure the existence of a graphics environment for XPCE. This library uses the `head-less' server Xvfb if there is no X-server in the environment.

Currently this library deals with Windows (where no explicit server is required) and Xfree using the Xfree socket naming conventions. Please send platform-specific code to info@swi-prolog.org