xemacs-21.4 / vms / VMSNOTES

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See the file VMSINSTALL for VMS installation information.

* Deficiencies of VMS GNU Emacs

All GNU Emacs features which on Unix work by running a Unix utility
in a subprocess currently do not work on VMS.

These include Dired, listing a file directory, reading and sending
mail, reading and posting netnews, spelling correction, displaying the
time and load in the mode line, queueing output for printing, and the
`sort-columns' command.  Naturally, the commands to view Unix manual
pages and execute Unix shell commands also do not work.

It is not possible to fix these problems in a general way on VMS
because they involve interfaces to parts of the operating system which
work very differently on VMS.  Each feature must be reimplemented

I hope that someone will send me an implementation for directory listing
on VMS.  This should not be very hard to do.  Most of the code you need
is already provided in [.src]dired.c.

The normal commands for running an inferior shell or lisp with I/O
through an Emacs buffer do not work on VMS, but you can instead create
a DCL subprocess which does I/O through an Emacs buffer and get a
similar effect.  See the file [.lisp]vms-patch.el.

* Specifying terminal type.

To specify a terminal type for Emacs that is not known to VMS,
define the logical name EMACS_TERM with the terminal type as value.
Terminal types are looked up in the termcap data base, which is
found as the file `[etc]termcap.dat' in the Emacs distribution.

* Specifying file names.

GNU Emacs accepts both Unix and VMS file name syntax.  Most Lisp
code that runs in Emacs uses Unix syntax so it can run everywhere.
Users on VMS will generally type file names with VMS syntax.

The EMACSLOADPATH logical name, if you use it, should contain
directory names in Unix syntax, separated by commas.

find-file prompts with the current directory.  You can then type a
relative directory spec to get somewhere else in the hirearchy.  For

Find File: emacs_library:[src][-.lisp]startup.el

is converted to emacs_library:[lisp]startup.el by
expand-file-name.  The basic rule is:  
][- is treated like /.. (dir:[file.sub][-.other] ==> dir:[file.other],
                         dir:[file.sub][-] ==> dir:[file])
][. elides the ][ (dir:[file][.sub] ==> dir:[file.sub])
][alpha backs up to the previous [ (dir:[file][other] ==> dir:[other])
a colon appearing after a ] forces a new "root" disk.
	(dev:[file]dev2:[other] ==> dev2:[other])
expand-file-name also tries to be smart about decnet node names,
but this is not yet known to work.

* A possible problem.

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.  If this file does not have appropriate access,
Emacs may think that you cannot write any files.