BSD lpr is prevented from printing PDF files
At least in GTK v3.22.30, the code disallows attempts to print PDF and PS files using the lpr backend. Although it is not easy or possible for GTK to determine if the printer can print these formats by querying lpr, the print backend should allow lpr to try.
There are two uses cases:
- A filter is being used by lpr to process the files prior to printing them. Personally, I am using a script to do this.
- The printer can print PDF and PS files directly. There are many printers that can print these format, so GTK should allow for the possibility.
This was detailed in https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=231110 with two possible patches. I am attaching the patch that accepts both formats. accepts-pdf-ps.patch