This directory contains shell scripts and news entries to update the editor
from whatever version you have to the current version.  Each shell script
is the output from a diffdir -e.  They should be run with csh, e.g.
	csh 2.9-2.10
to apply one update.  If you are running, say, 2.8 and you want 2.10
you should run 2.8-2.9 and then 2.9-2.10.

Complete sources to 2.10 and 3.3 are provided in ../ex2.10 and ../ex3.3.
If problems arise use these sources.  The advantage to a diffdir is that
it's shorter and quicker to send via uucp or whatever at 300 baud.
The diffdirs try not to mung your makefiles, since each flavor of unix
tends to need a separate makefile.

The 2.* versions fit on an 11/70,  the 3.* versions need a vax or an 11/70
with overlay software.
2.9 is slightly bigger than 2.10, 2.10 will fit on a v7 system with LISPCODE
and CHDIR turned on, 2.9 has to have LISPCODE turned off.

Notes on which version to run how on different flavors of UNIX:

11/23, 11/34 and 11/40:  not supported.  Version 1.1 worked on them, but was
	written for v6 and probably would need quite a bit of work for v7.
	It is claimed that the overlay software in ../overlay will make it
	possible to run vi on such a processor, but it has not been tested
	recently and you're on your own here.

v6:	Use 2.10 with the libretro package.
	Be sure to fix the include file sgtty.h
	in the libretro package by taking out CBREAK.
	2.10 tries to use it if it is defined.
	The upgrade directory contains such a fixed libretro.
	NOTE: the standard v6 cc cannot recompile the editor.
	You will need a v7 or a typesetter C compiler, or else
	must use the binaries supplied.

PWB 1.2: Treat this just like v6.  This goes for 1.0, 1.1, etc.
	The PWB 1.2 C compiler is the same as the typesetter C
	compiler, so there should be no trouble recompiling.

v7 PDP-11: Use 2.10 with makefile.v7.  You will have to make your cc
	have a larger symbol table to get ex_io to compile with cc,
	otherwise you can use pcc.  If you use pcc don't expect to get
	LISPCODE to fit.  See makefile.v7 for more details on this.

PWB 2.0: Treat this just like v7, but add -DUSG to the makefile's CFLAGS.
	The pwb system is missing CBREAK and TIOCSETN, so you won't be
	able to type ahead or rubout typeout in visual mode as well.
	The last version of ex to be tested on a PWB system was 2.8,
	as of this writing.

UNIX/32V: Use 3.3 with makefile.novm.  You can use makefile.vm if you
	prefer, this will make a much (15K) bigger editor and compile
	the error messages incore instead of making a strings file.
	3.4 will probably use features of VM/UNIX that will prevent
	this flag being turned on on non-vm systems.

VM/UNIX: Use 3.3 with makefile.vm.

UNIX/TS: Ex hasn't been gotten running yet on UNIX/TS to my knowledge.
	Something about : not erasing what's on the echo line.
	Anyway, use 3.3 if on a vax and 2.10 if on an 11.  Since UNIX/TS
	is a USG product it will probably be necessary to use -DUSG.
	The CBREAK and TIOCSETN features are missing here too.  Sigh.