Improve handling of the roff(7) "\t" escape sequence:

* Parsing macro arguments has to be done in copy mode,
  which implies replacing "\t" by a literal tab character.
* Otherwise, render "\t" as the empty string, not as a 't' character.

This fixes formatting of the distfile example in the oldrdist(1) manual.
This also shows up in the unzip(1) manual as one of several issues
preventing the removal of USE_GROFF from the archivers/unzip port.
Thanks to espie@ for attracting my attention to the unzip(1) manual.

1 files changed, 1 insertions, 0 deletions

diff --git a/chars.in b/chars.in
index 0d6959de..28a37eaa 100644
--- a/chars.in
+++ b/chars.in
@@ -42,6 +42,7 @@ CHAR("&",			"",		0)
 CHAR("^",			"",		0)
 CHAR("|",			"",		0)
 CHAR("}",			"",		0)
+CHAR("t",			"",		0)
 
 /* Accents. */
 CHAR("a\"",			"\"",		779)