Hi Paul, At 2022-11-25T18:18:46-0800, Paul Eggert wrote:
Thanks for the info about groff. You're right, tzdb man pages are supposed to be portable to both groff and traditional troff. For the latter I test with /usr/bin/nroff and /usr/bin/troff on Solaris 10, which is the oldest troff I know that is still supported.
I'm curious to know what that support looks like. Is there evidence of any _development_?
If we did that, Groff would set a source string like "\*-\*-help" as "−−help", with two instances of U+2212 MINUS SIGN instead of U+002D HYPHEN-MINUS. Therefore people couldn't cut and paste code examples out of HTML or PDF, and into the shell.
This hasn't been true for PDFs produced by groff for about 10 years.[1][2] You can copy a U+2212 minus sign and it will paste as a U+002D.
"\f(CW-\fP" is used instead of plain "-" because when the output is PDF, it is more clearly visible to humans as a hyphen-minus instead of as a hyphen (U+2010 HYPHEN).
Okay. It's a shame that's necessary.
Most people won't see a difference because groff 1.22.4 (and earlier releases going back to, I think, 2009) the man(7) macro package remaps the hyphen to the minus sign on the 'utf8' output device.
I noticed the abovementioned problem with PDF output, and I still see it with groff 1.22.4.
Some distributors do violence to the man.local file. But I am not a PDF expert; for this I'll have to turn as I often do to Deri James, who also wrote the gropdf output driver. Deri, what's a good way to root-cause the issue Paul describes? If I prepare the following document: $ cat EXPERIMENTS/minus-and-hyphen.man .TH foo 1 2022-11-25 "groff test suite" .SH Name foo \- frobnicate a bar .SH Description Copy and paste me: foo\-bar-baz. and render it with "groff -Tpdf -man" using either groff 1.22.4 or groff Git, then when I copy-and-paste "foo-bar." from the document to a shell prompt, I get this: $ echo foo-bar-baz. | od -c 0000000 f o o - b a r - b a z . \n 0000015
I see a different issue with groff 1.22.4 on Ubuntu 22.10: I cannot easily see the difference between "\f(CR-\fP" and "\f(CR\-\fP" on output to PDF. If I cut from the output PDF and paste into Emacs or the terminal, the former is indeed U+002D and the latter U+2202 and the difference is readily visible in Emacs or the terminal;
That's odd. This definitely is not consistent with the groff 1.22.4 behavior I'm familiar with. I find the minus sign and hyphen glyphs fairly distinguishable. I modified my example file above to switch to the CR font. Attaching (cropped, 7.7KiB) screenshot.
but it's not readily visible in the PDF. However, this glitch is not a serious issue for man pages since examples always contain hyphen-minuses not minus signs, so I didn't worry about it. I assume that it's yet another font thing, since the problem doesn't occur in the default Roman font.
Possibly; when fonts aren't embedded in the PDF, we're at the mercy of whatever the renderer supplies. groff 1.23 will be shipping a 380-page compilation of all its man pages in PDF, and it embeds the fonts; I am hopeful that this will provide a reliable basis for comparisons so that we can better track down issues like the ones above. Regards, Branden [1] Commit: https://git.savannah.gnu.org/cgit/groff.git/commit/?id=4536678ce5713907304ad... [2] One explanation: https://lists.gnu.org/archive/html/groff/2018-05/msg00076.html
