2016.10.07 21:38 "Re: [Tiff] Suppress warning about old-style JPEG compression", by Bob Friesenhahn
so configure definitely does not read this file. By reading tif_win32.c, I determined that I need to define TIF_PLATFORM_CONSOLE, but there seems to be no specific mechanism for that in configure, so I just added -DTIF_PLATFORM_CONSOLE=1 to my CPPFLAGS and tiffcp now writes errors to stderr.
When using unix-style configure, there is a configure option --disable-win32-io which causes tif_unix.c to be used rather than tif_win32.c. This should also avoid the popups.
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