!TITLE Preparing your own material
!      In its simplest form, VIEW can be used in much the same way as
!LOOK. You give the command
!         VIEW(filename)
!and VIEW prints the first 20 lines and then awaits further instructions.
!Unless the file has been structured as described below, VIEW will
!simply split it into 'continuation' pages, addressable by typing /n.
!
!
!<Structuring with Directives
!     You can use directives to structure a character member into
!     a 'preface' followed, optionally, by one or more 'sections'.
!     The preface is all the lines of text from the start of the member
!     to the first section.
!
!     Division into sections is accomplished by using brackets as
!     follows:
!
!
!        preface introducing sections 1, 2, ...
!
!        !< name of section 1
!           content of section 1
!        !>
!
!        !< name of section 2
!           content of section 2
!        !>
!                                       etc
!
!
!Any section can be subdivided by using more pairs of brackets within
!the outer brackets eg
!
!        preface introducing sections 1, 2,...
!        !< name of section 1
!            preface introducing sub-sections 
!            1.1, 1.2,...   of section 1
!        !< name of section 1.1
!            content of section 1.1
!        !>
!        !< name of section 1.2
!            content of section 1.2
!        !>
!        !>
!        !< name of section 2
!                 etc
!
!Such subdivisions can be extended to any depth, the 'content' of each
!section being a preface optionally followed by one or more subsections.
!
!
!
!
!     If the later parts of a file are left unstructured, the earlier
!     structured part is the only part which can be VIEWed. An extreme
!     case of this is when a file contains as the only directive the
!     terminator !> at the start of a line. The text up to that
!     terminator is then treated as a 'preface' (split up into pages by
!     VIEW if it is long enough) and the text after the terminator is
!     not VIEWable.
!>
!<Structuring using PD files
!     When VIEW is used on a PD file, it lists the (viewable)
!     members in alphabetical order and numbers them 1, 2, 3...
!     Then, to view a specific member, you just type the
!     corresponding number or name.
!
!     If the PD file has a member called 'PREFACE', this is listed in
!     full before the names of the other members.
!
!     It is appropriate to observe here that EMAS allows a member
!     of a PD file to be another PD file, to any depth and VIEW
!     operates similarly at each level.
!
!     The members are given in alphabetical order of member name.
!     However, you can give an 'alias' to a member by writing
!
!        !TITLE title to be used
!
!     as the first line of the member. A title specified in the
!     PREFACE member serves as an alias for the name of the PD
!     file itself.
!>
!<Special Functions
!
!
!    The VIEW program has a number of built-in functions which can be
!    used to insert items like todays date in the material being viewed.
!
!
!    A function is written as {n} where n is an integer. The following
!    functions are available
!
!
!      1 Date          {1}
!      2 Time          {2}
!      3 User no.      {3}
!      4 Delivery      {4}
!      5 Surname       {5}
!      6 OCP           {6}
!      7 Terminal type {7}
!>
!<The !MAIL Directive
!     You can invite a viewer to comment on your file by including the
!     directive
!
!           !MAIL to [,subject]
!
!     in a suitable section, eg
!
!           !<Viewer's coments
!              If you wish to make any comments
!              about this file, please type them here.
!           !MAIL CUR999@2960,Comments on my file
!           !>
!
!     VIEW prompts the viewer for his comments, packages the text and
!     calls MAIL to transmit it.
!>
!<The !PAGE Directive
!   VIEW displays a section in 'pages' of 20 lines. To avoid having
!   awkward breaks in your text, you can either insert a suitable number
!   of blank lines or use the
!
!               !PAGE
!
!   directive which forces an 'end-of-page', any unfilled lines remaining
!   blank.
!>
!<The !STOP Directive
!   Sometimes it is not appropriate to display the 'contents' of a
!   section after displaying the 'preface' (as View normally does)
!   Further output can be suppressed by inserting the
!
!               !STOP
!
!   directive. This facility is used in section 1 of this file.
!>
!<Inserting Keys
!     By default, the words which comprise the title of a section are
!     inserted into the key directory. You can specify a different
!     set of words with the directive
!
!           !KEY word1,word2,...
!
!     You may specify more than one line of keywords. If you say only
!
!           !KEY
!
!     then no entry is made in the key directory for that section. The
!     !KEY directive must be used before the preface of a section.
!>
!<Efficiency considerations
!
!     When VIEW is entered, it builds directories to the file
!     and inserts them as extra members so that subsequent
!     requests to VIEW a particular section can be dealt with
!     rapidly.
!
!     If the PD file is subsequently changed, the next time
!     it is VIEW'ed by its owner the directories are recalculated
!     and replaced.
!
!     Consequently, the owner of a file which is being VIEW'ed
!     by other people, MUST remember to keep the directories
!     up to date by VIEWing the file after making changes.
!
!>
!<Pointing at a subsidiary file
!      
!
!
!     You do this by including a dummy section of the form
!
!                 !<>filename [,view commands]
!
!     Note: the filename and any commands are not inserted
!     into the key directory.
!
!     When you return from VIEWing the file, by typing R,
!     you go 'up'
!>
!<The !SKIP Directive
!     When a (PD) file is being used simply to point at other files,
!     as in the case of SUBSYS.VIEWBASE, there are too many sections!
!     This problem can be avoided with the !SKIP directive. If a
!     member has the form
!
!           !SKIP
!           !<>filename [,commands]
!
!     then viewing that member results in viewing file filename.
!>
!<Aesthetic considerations
!
!
!     It is easy to set up some kind of file to be viewed
!     but you dont get the best effect quite so easily!
!  
!     Remember that your material will be displayed in
!     20 line chunks.   Try and make this a logical division.
!
!     Also remember that typically a terminal's line length
!     is 72 characters.  Lines longer than this will be
!     displayed but will wrap round and upset the line count.
!
!     Lines longer than 100 characters are truncated.
!
!     To make the *name facility most effective,
!     choose your names to be
!                  short,
!                  meaningful
!   and            unique.
!>