Advanced Server Commands

Chapter IV Table of Contents

A. The VMS System Editors: EVE, EDT, and WPS

B. Using EVE

C. LOGIN.COM

D. Symbols and Logical Names

A. The VMS System Editors: EVE, EDT, and WPS

The primary system editor on CSCWWW is EVE (supposedly an acronym for "Extensible VAX Editor"). The EVE editor can be used with several different settings for which keystrokes evoke which commands. One of the interfaces emulates EDT (the old standard VMS default editor), one emulates WPS (the ALL-IN-1 editor), and the third one is "standard EVE." New departmental accounts on CSCWWW are created with a LOGIN.COM that includes definitions for three symbols, one to invoke each interface of the editor: EDT, EVE, WPS. Section B of Appendix II includes these definitions in its examples. For ALL-IN-1 users, the WPS command, in particular, has the advantage of giving you an editor that is very similar to WPS-PLUS in ALL-IN-1 (and identical to the editor for the ALL-IN-1 "LSV" LISTSERV Simplifier).

B. Using EVE

$ WPS LOGIN.COM

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The symbol, "MACWP", defined in the standard LOGIN.COM, is used with HTML files that have been prepared by Macintosh WordPerfect V 3.5, using the HTML Export feature. Such files are best transferred to CSCWWW as if they were binary files. They will work correctly with the server as is, but cannot be easily modified with the system editor until the operating system has been told the truth about their internal format. The MACWP command serves this purpose.

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There are several keys that are particularly valuable when learning to use any of the three interfaces of EVE. The table below identifies the keys for the two most common environments: an IBM PC with an extended keyboard, using the standard key codes for ALL IN-1 as used by Computer Services' versions of MS-KERMIT, CUTCPIP, or any equivalent communications package, and an Apple Macintosh with an extended keyboard using VersaTerm in VT-320 mode, or any equivalent package.

The arrow keys do exactly what you expect. The insertion point is at the left edge of the character designated by the cursor, so that pressing the "<Delete>" key (next to the regular "=" key) will delete the character to the left of the cursor. Typing will insert characters starting with the current position of the cursor, with all characters to the right of the cursor being "bumped over." While you are inserting new text, the editor will wrap to the next line if you reach the end of the line, but it will not re-wrap the paragraph, and it will not re-wrap the rest of the current line. For readability and for reliable transfer, you should use the "<Return>" key to break any lines that have extended beyond the edge of the screen. Be very sure to keep each URL, including the quotes, on one line: many browsers are unable to follow links whose URLs have embedded line breaks.

C. LOGIN.COM

VMS provides mechanisms to customize your working environment, two of which we discuss in this section and the next section. Most of the mechanisms for customization are of greater interest to professional programmers than to web maintainers, but some of them may be worth learning how to do. Customizing the VMS environment is likely to be of greater value to those who use the system editor to maintain their HTML files and to those who login to VMS and change the default directory before transferring files (for example, with KERMIT and "piggyback" FTP), and is likely to be of less use to those who transfer files by direct FTP or Fetch.

Just before you first get to the VMS "$" prompt after logging in, the commands in the file "LOGIN.COM" are executed, if there is a file of that name in your login default directory. This functions like the file "AUTOEXEC.BAT" on an IBM PC, or the file "PROFILE EXEC" for VM/CMS accounts on the IBM mainframe, and permits you to define personal abbreviations for VMS commands. In general, you would establish these by revising the file "LOGIN.COM", so that it would include definitions for your personal abbreviations. Then, you would be able to type those short abbreviations instead of longer commands at the "$" prompt.

You can get up-to-date versions of the template files, including the standard LOGIN.COM, by the following command:

$ COPY WEB_MAINT:[WEBWEAVER.TEMPLATES]*.* []

For example, your LOGIN.COM file might look like the following:

$!
$ IF F$MODE() .NES. "INTERACTIVE" THEN EXIT
$! (if this is an FTP session, the following definitions don't help)
$!
$! define symbols for the system editor
$!
$ EVE :== EDIT/TPU/INIT=SYS$LOGIN:EVE$INIT.EVE
$ EDT :== EDIT/TPU/INIT=SYS$LOGIN:EVE$INIT.EDT
$ WPS :== EDIT/TPU/INIT=SYS$LOGIN:EVE$INIT.WPS
$!
$! define symbols for housekeeping commands
$!
$ WEB == "SET DEFAULT " + "''F$TRNLNM("SYS$LOGIN")'" - "]" + ".WWW]"
$ UP :== SET DEFAULT [-] ! even quicker to type than "CD .." on a PC
$ HOME :== SET DEFAULT SYS$LOGIN
$ PU2 :== PURGE/KEEP=2 ! current default only
$ CLEAN :== PURGE/KEEP=2 [...] ! and all subdirs of current default
$!
$! define symbols chosen for those with DOS and unix reflexes
$!
$ CD :== SET DEFAULT
$ MKDIR :== CREATE/DIRECTORY
$ MV :== RENAME
$ MORE :== TYPE/PAGE
$ PWD :== SHOW DEFAULT
$!
$! define symbol for Macintosh WordPerfect 3.5 HTML support
$!
$ MACWP :== SET FILE/ATTRIBUTE=RFM:STMLF
$!
$ EXIT
$!
$! template login.com file for CSCWWW
$!
$! 11/20/95 R. D. Piccard
$!


This example shows each line with a dollar sign ("$") as the first character; this is a requirement for commands included in LOGIN.COM. In each line, any characters following an exclamation point ("!") are ignored as "comments." Except for the first and last commands, the example commands above all define "symbols" (see the next section) that are abbreviations of standard VMS commands. The definition given here for "WEB" is one that works for everyone and has the effect of setting default to your own departmental [.WWW] subdirectory, regardless of the current default. (For on-line help in understanding how that definition works, start with "HELP LEXICAL".) The rules for quotes and apostrophes are quite arcane (as you can see from the VMS Mail forwarding address and the definition of "WEB"), and even experienced VMS users often have to try a few variations before getting the results they want!

The last symbol defined before the EXIT command, "MACWP", is used with HTML files that have been prepared by Macintosh WordPerfect V 3.5, using the HTML Export feature. Such files are best transferred to CSCWWW as if they were binary files. They will work correctly with the server as is, but cannot be easily modified with the system editor until the operating system has been told the truth about their internal format. The MACWP command serves this purpose.

You do not need to learn the system editor to create and maintain your LOGIN.COM file. It is a simple text file, and can therefore be maintained by the same techniques you use to maintain web HTML files. After revising it on your desktop machine, transfer it up to your login directory (notyour [.WWW] subdirectory) on CSCWWW.

D. Symbols and Logical Names

Your LOGIN.COM file may establish abbreviations that save you from having to remember and to type some rather elaborate commands. There are two different types of abbreviations, symbols and logical names, so we first discuss the distinction between them. (There is some conceptual overlap between symbols and logical names in VMS and environment variables in unix.)

Symbols are VMS variables that can take the place of commands, parts of commands, file names, or parts of filenames. Their most common use is as synonyms for commands or parts of commands. They are thus often grammatically verbs. They are established at the VMS level by assignment statements using "=", "==", ":=", or ":==". The doubled equals signs denote an assignment in global (process) context and those symbols remain valid until you logout. The single equals sign denotes an assignment in the context of the current command procedure only. The colon indicates string assignment, while its absence indicates numerical assignment (unless the righthand side of the expression is enclosed in quotes). This is why the examples illustrated for LOGIN.COM use ":==", they are useful only if valid after LOGIN.COM completes, and they create synonyms for long commands. A new value is established by executing another assignment statement. An existing value can be abolished without replacement by

$ DELETE/SYMBOL symbol

Logical names primarily take the place of node, device, directory, or filename specifications. (They can also be used, for example, to designate the recipient of a VMS MAIL message.) They are thus grammatically nouns. They are established by either of two VMS verbs, whose only difference is the order of the parameters:

$ ASSIGN meaning logical_name

and

$ DEFINE logical_name meaning

A new meaning is established for an existing logical name by executing another ASSIGN or DEFINE statement. The existing meaning of a logical name is dis-established by

$ DEASSIGN logical_name

To determine the current definition of a symbol, use the command

$ SHOW SYMBOL symbol

To determine the current definition of a logical name, use the command

$ SHOW LOGICAL logical_name

Various modifiers may be used with these SHOW commands. The on-line HELP facility describes them and provides examples.

    

Dick Piccard revised this file (http://www.ohiou.edu/pagemasters/memo85/chap4.html) on March 9, 2000.

Please E-Mail comments or suggestions to "acatec@www.ohiou.edu".