[200,200] RSX BASIC - MICHAEL REESE VERSION





          Overview:



          BASIC as implemented in the following files under RSX-11D is

          a highly upgraded version of what used to be a DECUS library

          program for DOS.  Full FILES-11 I/O is  supported  (although

          in  a  bastard  sort of way).  String functions and user de-

          fined functions are much more flexible than  in  either  the

          original  version or in DEC's BASIC-11.  A number of defici-

          encies and bugs in the original have been fixed.  Multi-user

          implementation  is  supported  with separate pure and impure

          areas.  This implementation of BASIC is highly  interpretive

          and  thus  is slow for number crunching (that's why you have

          FORTRAN).  It is however, highly  interactive  and  includes

          special  debugging  commands:   STEP and CON.  OVERLAY and a

          data preserving CHAIN are also supported.  A  clean  "break"

          feature can be implemented via the TT handler (more below).



          Files:



          BASIC0.MAC through BASIC4.MAC plus IDNTFY.MAC and  IMPUR.MAC

          are  the seven source files for the interpreter.  BASIC4.MAC

          implements the guts of the user  subroutine  CALL  statement

          plus  a set of specialized subroutines used at Michael Reese

          Medical Center.  This code can probably be  removed  with  a

          minimum  of work if space becomes a problem.  BASIC2 and BA-

          SIC3 will need the large MACRO assembler.



          BIGBASIC.CMD is a task build command file which may be tail-

          ored for an individual installation.  Note:  FORCOR is a re-

          sident library containing  the  command  string  interpreter

          among  other  things.   Modify this to use whatever resident

          library you might have (or none at all - all routines needed

          are in SYSLIB).



          Another set of command files is used to link a library  ver-

          sion  of BASIC.  First, an impure area STB is created by as-

          sembling IMPUR without the symbol definition  TASK=1.   This

          prevents  the global definition of .MOLUN and prevents prob-

          lems later on.  IMPURNOMO is then linked to form the  symbol

          table.   The  library  is then linked using bscpur.cmd.  Put

          the resulting TSK and STB files in SY:[1,1]  and  link  with

          BAS.CMD.   Ignore  the  resulting  TKB  error messages.  The

          BAS.TSK file can now be installed with different INC  values

          for optimized use, each one sharing the pure code.



          MSGEN is a program for generating and modifying an  MO  mes-

          sage  file for BASIC.  The current file is BASIC.MSG.  If no

          MO output is desired, modify BASIC0.MAC by removing the line

          defining  the symbol RSX11D.  This will produce numbered er-

          ror messages but no explanatory text.  This  conditional  is

          as  yet  untested.  If someone using an RSX-11M system needs

          to correct the procedure, I would appreciate  knowing  about




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          it.



          BASDOC is a program which extracts RUNOFF format source text

          from  the  macro  files  for  BASIC.   The  output is a file

          BASIC.RNO which, when processed  by  RUNOFF  (Michael  Reese

          version)  produces  a  fairly  complete  manual  for  BASIC.

          BASIC.DOC is such a manual.



          A BASIC break is now implemented via the ^C AST function  of

          the  V6.2  TT handler.  Note that the definition RSX11D=1 is

          used for  this  option.   It  should  work  this  way  under

          RSX-11M.   Also note that this break happens between succes-

          sively executed lines.  Thus a one line loop cannot be  bro-

          ken.



          If you have questions call:

                    Larry Simpson

                    Dept. of Medical Physics

                    Michael Reese Medical Center

                    2929 So. Ellis Ave.

                    Chicago, Ill. 60616

                    (312) 791-2515





OPERATING SYS  : RSX11D - IAS? - RSX-11M?

HARDWARE REQ'D : FP11

SOFTWARE FORM  : SOURCES AND COMMAND FILES

DOC. FORMAT    : RUNOFF (MICHAEL REESE VERSION)

VERSION        : 02NO77