1Note that all \[charXXX] entity names have been removed from the font files.
2They don't make sense for Unicode.
3
4The following entity from the original troff manual (by Ossanna and
5Kernighan) is unmapped:
6
7  bs    shaded solid ball (Bell System logo, AT&T logo)
8
9Character 0x002D has not been given a name because its Unicode name
10HYPHEN-MINUS is so ambiguous that it is unusable for serious typographic
11use.
12
13\[wp] has been mapped to 0x2118, because according to Unicode 4.1's
14NamesList.txt, U+2118 SCRIPT CAPITAL P is really a Weierstrass `p',
15neither SCRIPT not CAPITAL.
16
17The following line could be added; \[space] is known to devps but is not
18documented and not known to devdvi (actually, there is no space glyph within
19the TeX system).
20
21  space   24   0   0x0020
22
23devps maps \[a~] and `~' to `asciitilde', which is equivalent to 0x02DC, but
24this glyph is just too small.  We map them to 0x007E instead.
25
26devps maps \[a^] and `^' to `circumflex', which is equivalent to 0x02C6, but
27this glyph is just too small.  We map them to 0x005E instead.
28
29devps maps \[*U] to `Upsilon1', which is equivalent to 0x03D2.  We map it to
300x03A5 instead.
31
32devps maps \[*W] to `Omega', which is equivalent to either 0x2126 or 0x03A9.
33We map it to 0x03A9.
34
35devps maps \[*D] to `Delta', which is equivalent to either 0x2206 or 0x0394.
36We map it to 0x0394.
37
38
39Adding Unicode characters
40-------------------------
41
42Assume you want to use a Unicode character not provided in the list, say
43U+20AC. You need to do two things:
44
45- Add a line
46
47    u20AC   24   0   0x20AC
48
49  (the second column is computed as 24 * wcwidth(0x20AC)) to the file
50  R.proto, or, when groff is already installed, to the four fonts files in
51  $(prefix)/share/groff/<version>/font/devutf8/.
52
53- In your source file, use the notation \[u20AC] to access it.
54