I'm seeking for the _proper_ way to _signal_ a 404 to whatever visits the site (search engines, bots, etc.).
Right.... And you already shown that you know the proper way to signal a 301. You print 301. Now, do you still really not understand how to print 404? Let me explain how one can print 404. 
print 404;  # TADA! Magic!

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Printing an optional message and mandatory network end-of-lines is left as an excercise for the reader.

Please come back to the site if you have problems printing a different number!

In reply to Re^5: Doing a proper 404 redirect by JavaFan
in thread Doing a proper 404 redirect by DreamT

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