In general, no. Because in general, the X server (which DISPLAY is pointing at) may not even be running on the local machine.
But then again I'm interested in making the GUI version start automatically only if the/a X server is running on the local machine (unless explicitly stated differently by the user on the cmd line).

In reply to Re^7: How to detect X? by blazar
in thread How to detect X? by blazar

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