termcap description added

Makefile

@@ -72,7 +72,7 @@
 #
 #	from Makefile	7.13.1.3 (2.11BSD GTE) 1996/10/23
 #
-#	@(#)Makefile	1.49 (gritter) 2/19/05
+#	@(#)Makefile	1.50 (gritter) 2/20/05
 #
 
 #
@@ -207,8 +207,9 @@ OSTYPE	= -DVMUNIX
 #
 #TERMLIB	= ncurses
 #
-# The preferred choice for ex on Linux distributions and other systems that
-# provide a good termcap file is the 2.11BSD termcap library included here.
+# The preferred choice for ex on Linux distributions, other systems that
+# provide a good termcap file, or when setting the TERMCAP environment
+# variable is deemed sufficient, is the included 2.11BSD termcap library.
 #
 TERMLIB	= termlib
 

README

@@ -78,6 +78,33 @@ it would not result in any real improvements for usual the Unix platforms vi
 is targeted at, so it has not be done yet.
 
 
+Terminal capabilities
+=====================
+
+vi normally uses the termcap library to gather information about the
+capabilities of the terminal it is using. A BSD-derived termcap library
+is included with the vi distribution, and is usually the preferred choice.
+On some platforms, though, either no /etc/termcap file exists, or the file
+lacks up-to-date entries. In these cases, two workarounds are possible.
+First, vi can be linked against libcurses, libncurses, or libtermcap, if
+these provide access to a proper terminal information database. Second, it
+is possible to use the included termcap library with a TERMCAP environment
+variable that contains a complete termcap entry. Most terminals in current
+use provide a superset of DEC VT102 capabilities, so the following will
+normally work:
+
+TERMCAP="vt102|$TERM|dec vt102:"\
+'do=^J:co#80:li#24:cl=50\E[;H\E[2J:'\
+'le=^H:bs:cm=5\E[%i%d;%dH:nd=2\E[C:up=2\E[A:'\
+'ce=3\E[K:cd=50\E[J:so=2\E[7m:se=2\E[m:us=2\E[4m:ue=2\E[m:'\
+'md=2\E[1m:mr=2\E[7m:mb=2\E[5m:me=2\E[m:is=\E[1;24r\E[24;1H:'\
+'rs=\E>\E[?3l\E[?4l\E[?5l\E[?7h\E[?8h:ks=\E[?1h\E=:ke=\E[?1l\E>:'\
+'ku=\EOA:kd=\EOB:kr=\EOC:kl=\EOD:kb=^H:'\
+'ho=\E[H:k1=\EOP:k2=\EOQ:k3=\EOR:k4=\EOS:pt:sr=5\EM:vt#3:'\
+'sc=\E7:rc=\E8:cs=\E[%i%d;%dr:vs=\E[?7l:ve=\E[?7h:'
+export TERMCAP
+
+
 Multibyte locale support
 ========================
 
@@ -111,7 +138,7 @@ the erase key once after entering a multibyte character will result in an
 incomplete byte sequence.
 
 
-Gunnar Ritter                                           2/19/05
+Gunnar Ritter                                           2/20/05
 Freiburg i. Br.
 Germany
 <Gunnar.Ritter@pluto.uni-freiburg.de>