HP 3000 Manuals HP 3000 Manuals
Design of the Help System
The HP Desk help system comprises a series of help pages, each having a
unique number. They are installed and stored as privileged files secure
from unauthorized access in the group MAILHELP.HPOFFICE, with a C prefix.
A series of help directives determine the characteristics of the page,
and how each page links to others.
Help Pages
There are three kinds of page: menu, text, and extension pages. These
are explained in detail below.
Menu Pages
Menu pages contain an identifier and pointers that reference sub-menus or
text pages.
Once a page is installed, the help system reads the descriptions of the
referenced pages into the menu. This forms the list of options from
which a user can choose by typing a number. No text is contained in a
Menu page, apart from some introductory text which may optionally
introduce the list of options. A single menu can consist of up to 100
options. Up to 99 levels of sub-menu are possible below the main menu.
An example of a menu page is shown below:
$ID 0 "Help system main menu"
$TITLE "Help System Main Menu"
$SONS 550,600,1200,1600,2000,2400,2800,3200,3600,4000,4200
Type the item number and press <RETURN> to select an item from
the menu:
In this example, $ID is the help directive that identifies the page and
provides a description. $TITLE is a directive that provides a title for
the help page that is displayed on screen, and the $SONS directive points
to other menus or text pages. Lastly, some introductory text is
included.
Text Pages
Text pages contain an identifier and text. A text page contains all the
information on a particular topic. It may take one or more screens to
display.
A high degree of control is available over how help pages are displayed.
Pages can be displayed selectively to users of particular terminals, such
as block mode terminals, or members of specific capability groups, such
as the system administrator. The directives $TERMCAP and $GROUPS support
these features.
Extension Pages
Extension pages enable you to customize the help system by adding extra
options to menus or extra information to text pages. As such, an
extension page can take the form of either a menu page or text page--the
only distinguishing feature being a special identifier.
By default, an extension page appends to the end of a specified existing
page, and is displayed as an extension to that page. More than one
extension page can be appended to an existing page--and if this is done,
the extension pages are appended in numerical sequence. However, you can
insert a extension page into an existing page, by editing the existing
page to include a $TAG directive to mark the point of insertion.
Page Identifiers
There are 10000 help pages available for use, although in reality only a
few hundred are actually used. Each installed help page has a unique
identifier which, for menu and text pages, is a four-digit number. The
permitted range of identifiers is as follows:
0000-8999 These pages are reserved for use by Hewlett-Packard. This
does not, however, mean that you cannot use them, but a new
installation of HP Desk may overwrite them.
9000-9999 These pages are reserved for any new pages you write.
Hewlett-Packard will never use this range of identifiers.
The HP Desk help system is designed in a hierarchical tree structure,
with page 0 as the main help page, and the Hewlett-Packard installed
pages following.
Extension pages have identifiers of the form:
xxxx,yyy
where:
xxxx is the numeric identifier of the page to which the
extension is to append
yyy is the number that identifies the individual
extension page. Any extension pages you write must
have extension identifiers ending in 9, that is
nnnn,nn9.
The page identifier is always displayed with a help page, in the top
right-hand corner when you view the page. This enables you to easily
identify a page, if you want to edit it.