

Lexicon                    Introduction                   Lexicon




The Mark  Williams Lexicon is a new  approach to documentation of
computer software.  The Lexicon is designed to improve documenta-
tion and  eliminate some  limitations found in  more conventional
documentation.

***** How to Use the Lexicon *****

The Lexicon consists  of one large document that contains entries
for  every  aspect of  COHERENT.   You will  not  have to  search
through a  number of different manuals to find  the entry you are
looking for.

Every entry  in the  Lexicon has  the same structure.   The first
line gives the name of the topic being discussed, followed by its
type (e.g., CCoommmmaanndd).

The next  lines briefly describe  the item, then  give the item's
usage, where  applicable.  These are followed  by a brief discus-
sion of the item, and an example.

Cross-references  follow.  These  can be to  other entries  or to
other texts.   Diagnostics and notes,  where applicable, conclude
each entry.

Internally, the Lexicon has a tree structure.  The ``root'' entry
is the  present entry, for  LLeexxiiccoonn.  Below this  entry comes the
set of _O_v_e_r_v_i_e_w  entries.  Each Overview entry introduces a group
of entries; for example, the Overview entry for ssttrriinngg introduces
all of  the string functions and macros, lists  them, and gives a
lengthy example of how to use them.

Each entry cross-references  other entries.  These cross-referen-
ces point  up the documentation tree,  toward an overview article
and,  ultimately, to  the entry  for  Lexicon itself.   They also
point down the tree to subordinate entries, and across to entries
on related  subjects.  For example, the  entry for ggeettcchhaarr cross-
references SSTTDDIIOO, which is its Overview article, plus ppuuttcchhaarr and
ggeettcc, which  are related  entries of  interest to the  user.  The
Lexicon is designed  so that you can trace from  any one entry to
any other,  simply by following the  chain of cross-references up
and down the documentation tree.

See the  logic tree  that is included  in the appendices  to this
manual for the full tree structure of the Lexicon.

***** Use the Lexicon *****

If, while  reading an entry, you encounter  a technical term that
you do  not understand,  look it up  in the Lexicon.   You should
find an  entry for  it.  For  example, if a  function is  said to
return a data type float and you do not know exactly what a float
is, look  it up.  You  will find it  described in full.   In this
way, you should increase your understanding of COHERENT, and make
your programming easier and more productive.


COHERENT Lexicon                                           Page 1




Lexicon                    Introduction                   Lexicon




***** Overview Articles *****

The Lexicon  includes the  following overview articles.   Look at
the appropriate  overview article for information  on the subject
in which you are  interested.  The overview article will give you
an overview of the topic, and tell you which Lexicon articles you
should read to find detailed information.


     C language
     commands
     definitions
     device drivers
     environmental variables
     file formats
     system maintenance
     technical information







































COHERENT Lexicon                                           Page 2


