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The example program TSTHLP, together with the sample library demo.shl,
shows a typical help session.
Type the following command:

This will produce an announcement, followed by the question:
Name of help library?
Give the reply:

This will produce a ":" prompt; enter one of the following:
- <CR> to display the top-level help text and subtopics,
- a topic name to display the help text for the nominated topic, or
- a period to terminate the program.
At other prompts, enter:
- a subtopic name to display the text for that subtopic,
- <CR> to move back one level in the hierarchy,
- question mark "?" to
redisplay the text for the current topic, or
- ellipsis "..." to display all
the text below the current point in the hierarchy.
The topic and subtopic names in the library are called
``keywords''. When searching for a given keyword, it is unnecessary to
give the full name. The rules for abbreviating keywords are as follows:
- The simplest form of abbreviation is to give only the first few
characters. Thus "FRED" is a valid
abbreviation of "FREDERIC".
- A keyword can be made up of one or more ``words'' separated by an
underscore. Each such word can be abbreviated individually. Thus
"A_D" is a valid abbreviation of "ANNO_DOMINI".
- The characters "%" and "*"
match, respectively, any single
non-space character or any sequence of such characters.
- The character "
"
in the entered string is itself ignored but
causes the next character to be accepted literally (but not space).
This means that the various special characters can appear in keywords;
however, exploiting this feature is not recommended.
- If a word from the entered string contains but does not end with a
"*" wildcard, it must not be truncated.
Thus, although "SAM" and "S*E" are both valid
matches for "SAMPLE", "S*PL" is not.
This feature allows abbreviations
to be used which unambiguously specify the end of the string as well as
the beginning.
- Neither the keyword in the library nor the string entered may
contain leading or embedded spaces.
When the entered string is a valid abbreviation of
more than one topic but is not an
exact match for any topic, all the matched
topics are reported. Thus "* * *" would display all the level-three
topics, and "..." would display every topic in the library.
When the entered string is an exact match for a topic, no further
matches are reported once the exact match has been found.
Keyword comparisons are not case-sensitive: "aBc" is a valid match for
"ABC" for example.

Next: CREATING A HELP LIBRARY
Up: HLP --- Interactive Help System
Previous: Package Contents
HLP --- Interactive Help System
Starlink User Note 124
P. T. Wallace
13th June 1995
E-mail:ptw@star.rl.ac.uk