* Installing GNU Emacs from a VMS install kit

If you receive a VMS distribution tape containing an install kit, you
can restore Emacs and run it immediately on any VMS system 4.2 or newer.
The installation command file will automatically rename certain files
whose names must vary according to the version of VMS in use.

However, it is not certain we will have the install kit developed
soon, so until that is done, you may receive an ordinary BACKUP
saveset instead.

* Installing GNU Emacs from an ordinary VMS BACKUP saveset

If you receive a VMS distribution tape in VMS BACKUP interchange
format you can restore Emacs and run it on VMS versions 4.2 or newer
after executing a few commands.  What you must do depends on the
VMS version (one procedure for VMS 4.2 or 4.3; another procedure
for newer VMS versions).

For VMS versions 4.4 and up, make sure the file
SYS$SYSTEM:RIGHTSLIST.DAT has WORLD:R access.  Emacs reads this file
to check file access.

In order to compile Emacs with the VMS C compiler, you will need a
pagefile quota of around 22000 pages, plus enough swap space to handle
that.  (This was in VMS 5.1-1, with 5 meg of physical memory.)  See
HELP SYSGEN CREATE and HELP SYSGEN INSTALL for more information.

Choose a directory to restore to, say DEV:[LIB].  Do:

	$ mount/foreign mta0:
	$ backup/log mta0: dev:[lib...]

Now, if you are using VMS version 4.4 or later, set your default to
the directory DEV:[LIB.EMACS] and run the command file
DEV:[LIB.EMACS]ALLRENAME.COM:

	$ set default dev:[lib.emacs]
	$ @allrename [...] "_" "-"

This renames all files in the Emacs distribution from their old-VMS
names (containing `_' characters) to their new-VMS names (containing
`-' instead).

Now, edit DEV:[LIB.EMACS]EMACS.COM.  Replace the definition of
EMACS_LIBRARY with the appropriate device and directory.  The
definition initially reads as follows:

	$ define /translation=concealed emacs_library	sys$device:[emacs.]

You would replace this with:

	$ define /translation=concealed emacs_library	dev:[lib.emacs.]

Now execute the command file DEV:[LIB.EMACS]EMACS.COM.  This defines
a command EMACS that runs a suspendable permanent Emacs.  To
fully install Emacs, you must arrange for users to run this file
on login, or arrange for this file to be run when the system boots.

The distribution contains an Emacs executable in
DEV:[LIB.EMACS]EMACS.EXE.  It uses DEV:[LIB.EMACS]EMACS.DUMP every time
it runs.  The EMACS.EXE has been linked with the non-sharable C
library, so it should run on any VMS V4.4+ system, whether or not the
C compiler exists.  The .OBJ files are all there, so you can relink
with /debug if you want to have fun.

A few C source files contain compilation conditionals that depend
on the version of VMS.  We have compiled these files specially for
VMS version 4.2 (or 4.3) in object files with extension .JBO.
So to run on VMS 4.2, rename all the .JBO files to .OBJ, then
link and build Emacs as described in DEV:[LIB.EMACS.SRC]VMSBUILD.

	$ set def [.src]
	$ rename *.jbo *.obj
	$ @precomp
	$ @link
	$ @build
	$ rename temacs.exe [-]emacs.exe
	$ rename temacs.dump [-]emacs.dump

To be clean, you should also edit the file [.SRC]CONFIG.H to #include
the file S_VMS4_2.H.  Then the proper conditionals will be activated
if you ever recompile.

* Moving a Unix distribution to VMS.

Moving a Unix distribution to VMS is mostly a matter of transferring
the files to the VMS system, but with old versions of VMS (prior to
4.4) it is a little more complicated because some of the file names
used on Unix are not supported by VMS.  Every `-' in a Unix file name
must be changed to a `_' on VMS.  (In VMS versions 4.4 and up, this is
not necessary, since `-' is allowed in file names.)

A few other changes must be made regardless of the version of VMS:

1) Copy the file [.SRC]VMSPATHS.H to [.SRC]PATHS.H, replacing any existing
file PATHS.H in that directory.

2) Delete any file [.SRC]CONFIG.H and replace it with a copy of
CONFIG.H-DIST.  Then edit this file so it specifies `m-vax.h' as the
second include file and for the first include file one of
`s-vms4-0.h', `s-vms4-2.h', `s-vms4-4.h' or `s-vms5-5.h'.  (Use the
highest version not greater than the VMS version you are running.  For
VMS versions prior to 4.4, the `-' characters must be replaced with
`_'.)

You can now compile, link, build and install Emacs as described in
[.SRC]VMSBUILD..

* Moving a VMS distribution to Unix.

Delete all .OBJ files, and PATHS.H and CONFIG.H.  Then copy the
remaining files, changing each `_' in a file name to `-`.  Unix will
allow filenames with `_' but Emacs will not work with them!

Names which on VMS end in a period (have a null extension) should
have no period on Unix.  Thus, "YMAKEFILE." becomes "ymakefile".

VMS file names are case-insensitive.  On Unix, case is significant.
Most of the file names must be in lower case or they will not work.
There are only a few exceptions:

1) CHANGELOG. becomes ChangeLog
2) MAKEFILE. becomes Makefile
3) TAGS. becomes TAGS
4) Files of English text with null extensions keep their names
 in upper case.  For example, README. becomes README and
 [.ETC]GNU. becomes GNU