HELP is used to get information about commands and topics, or to produce a hardcopy manual for reference. A command is, of course, a process that can be executed directly by VISTA. A topic is a set of information about some aspect of VISTA. For example, this information appears under the command 'HELP', while introductory material about procedures is found under the topic 'Procedures'.
The simplest form of the command is HELP with no arguments. This form of the command will produce on your terminal a list of the the major categories of VISTA commands (e.g., INTRODUCTION, IMAGE PROCESSING, SPECTROSCOPY, etc.) The program then will display the names of the commands under each category. After that, you can get help on a particular command or topic by typing its name - the names are shown on the terminal.
To get information on a particular command or topic, type HELP followed by
the name of the command or topic. If you want help on several subjects,
type them all on the command line. The words should be separated with
blanks, as is usual with VISTA commands. Three examples are:
The first line of information about commands contains a line beginning with 'Form: ', which spells out the syntax of that command in detail. Following this are more detailed explanations of the workings of that command. These paragraphs form an example of an entry readable by the HELP command. Important: Keywords listed in square brackets (as [ALL], above) are OPTIONAL; they modify the operation of the command, if desired, but need not be specified under all circumstances.
The output of this program can be redirected. (The output redirection mechanism is described in the section 'REDIRECT' - type HELP REDIRECT if you are on a terminal.)
New to Version 4.2 is the capability to run the HELP program standalone. This is particularly useful in a workstation environment where you may wish to have one window dedicated to the VISTA HELP. This program is named vistahelp; check with your local VISTA manager for its location.
Examples
If there are several commands or topics which begin with a pattern given on
the command line, the helpfiles for all those commands will be printed.
For example,
will list the help files for COPY, COPW, CONTINUE, CONTOUR, and any other
commands which begin with the letters 'CO'. Exception: If there are
several commands which begin with the pattern you give, but the pattern
matches exactly the name of one command or topic, only the match will be
printed. For example, HELP PRINT will give you information on PRINT only,
even though there is another command (PRINTF) which begins with the same
pattern.
The character '?' can be used as a abbreviation for the HELP command. See the section '?' in the manual (or type 'HELP ?' if you are on a terminal.)