Note that all `charXXX' entity names have been removed from the font files.
They don't make sense for Unicode.
The following from the original troff manual (by Ossanna and Kernighan) is
unmapped:
\(bs shaded solid ball (Bell System logo, AT&T logo)
Character 0x002D has not been given a name because its Unicode name
"HYPHEN-MINUS" is so ambiguous that it's unusable for serious typographic use.
\(wp has been mapped to 0x2118, because according to unicode.org's
NamesList-3.0.0.txt, U+2118 "SCRIPT CAPITAL P" is really a Weierstrass p,
neither SCRIPT not CAPITAL.
The following line could be added; "space" is known to "devps" but are not
documented and not known to "devdvi" (actually, there is no space glyph
within the TeX system).
space 24 0 0x0020
"devps" maps \(a~ and ~ to asciitilde, which is equivalent to 0x02DC, but
this glyph is just too small. We map them to 0x007E instead.
"devps" maps \(a^ and ^ to circumflex, which is equivalent to 0x02C6, but
this glyph is just too small. We map them to 0x005E instead.
"devps" maps *U to Upsilon1, which is equivalent to 0x03D2. We map it to
0x03A5 instead.
"devps" maps *W to Omega, which is equivalent to either 0x2126 or 0x03A9.
We map it to 0x03A9.
"devps" maps *D to Delta, which is equivalent to either 0x2206 or 0x0394.
We map it to 0x0394.
Using unnamed characters
------------------------
Assume you want to use a Unicode character not provided in the list, say
U+20AC. You need to do two things:
- Add a line
--- 24 0 0x20AC
(the second column is computed as 24 * wcwidth(0x20AC)) to the file
R.proto, or, when groff is already installed, to the four fonts files in
$(prefix)/share/groff/<version>/font/devutf8/.
- In your source file, use the notation \N'8364' where 8364 is the decimal
representation of 0x20AC.