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Some invalid ‘file’ arguments to ‘postscript()’ and ‘xfig()’ opened a file called ‘NA’ rather than throw an error. These included ‘postscript(NULL)’ (which some people expected to work like ‘pdf(NULL)’).
Passing ‘filename = NA’ to ‘svg()’, ‘cairo_pdf()’, ‘cairo_ps()’ or the Cairo-based bitmap devices open a file called ‘NA’: it now throws an error.
‘quartz(file + NA)’ opened a file called ‘NA’, including when used as a Quartz-based bitmap device. It now gives an error.