Add \*(Ai (ANSI) and \*(Px (POSIX) predefined strings, which are part of

groff's tmac.doc package.  Originally noted by Matthew Dempsky.
Feedback by Jason McIntyre, joerg@, and schwarze@.  Also add some
documentation about predefined strings, tweaked by schwarze@.

1 files changed, 2 insertions, 0 deletions

diff --git a/chars.in b/chars.in
index 5b7d99de..33ff760b 100644
--- a/chars.in
+++ b/chars.in
@@ -375,6 +375,8 @@ STRING("right-parenthesis",	")",		41)
 STRING("right-singlequote",	"\'",		8217)
 STRING("rp",			")",		41)
 STRING("Tm",			"(Tm)",		8482)
+STRING("Px",			"POSIX",	0)
+STRING("Ai",			"ANSI",		0)
 
 /* Lines. */
 CHAR("ba",			"|",		124)