README file for
Bywater BASIC Interpreter/Shell, version 2.20
---------------------------------------------
Copyright (c) 1993, Ted A. Campbell
for bwBASIC version 2.10, 11 October 1993
Version 2.20 modifications by Jon B. Volkoff,
25 November 1995
DESCRIPTION:
The Bywater BASIC Interpreter (bwBASIC) implements a large
superset of the ANSI Standard for Minimal BASIC (X3.60-1978)
and a significant subset of the ANSI Standard for Full BASIC
(X3.113-1987) in C. It also offers shell programming facilities
as an extension of BASIC. bwBASIC seeks to be as portable
as possible.
This version of Bywater BASIC is released under the terms of the
GNU General Public License (GPL), which is distributed with this
software in the file "COPYING". The GPL specifies the terms
under which users may copy and use the software in this distribution.
A separate license is available for commercial distribution,
for information on which you should contact the author.
IMPROVEMENTS OVER PREVIOUS VERSION (2.10):
* Plugged numerous memory leaks, resolved memory overruns and allocation
difficulties.
* General cleanup and bug fixes, too many to list in detail here.
The major problem areas addressed were:
- RUN command with file name argument
- nested and cascaded FOR-NEXT loops
- PRINT USING
- EOF, LOF functions
- string concatenation
- operator hierarchy
- multi-level expression evaluation
- hex constant interpretation
- hex and octal constants in INPUT and DATA statements
* Added a CLOSE all files feature (when no argument supplied).
* Added a unary minus sign operator.
* Added a MID$ command to complement the MID$ function.
* Added a RENUM facility in a standalone program.
* Added checking in configure for unistd.h (important on Sun systems).
OBTAINING THE SOURCE CODE:
The source code for bwBASIC 2.20 is available immediately by
anonymous ftp. To obtain the source code, ftp to site ftp.netcom.com,
cd to pub/rh/rhn and get the file bwbasic-2.20.uu. Or you may receive
a copy by e-mail by writing to Jon Volkoff at eidetics@cerf.net.
COMMUNICATIONS:
email: tcamp@delphi.com (for Ted Campbell)
eidetics@cerf.net (for Jon Volkoff)
A LIST OF BASIC COMMANDS AND FUNCTIONS IMPLEMENTED in bwBASIC 2.20:
Be aware that many of these commands and functions will not be
available unless you have set certain flags in the header files.
ABS( number )
ASC( string$ )
ATN( number )
CALL subroutine-name
CASE constant | IF partial-expression | ELSE
CHAIN file-name
CHDIR pathname
CHR$( number )
CINT( number )
CLEAR
CLOSE [[#]file-number]...
CLS
COMMON variable [, variable...]
COS( number )
CSNG( number )
CVD( string$ )
CVI( string$ )
CVS( string$ )
DATA constant[,constant]...
DATE$
DEF FNname(arg...)] = expression
DEFDBL letter[-letter](, letter[-letter])...
DEFINT letter[-letter](, letter[-letter])...
DEFSNG letter[-letter](, letter[-letter])...
DEFSTR letter[-letter](, letter[-letter])...
DELETE line[-line]
DIM variable(elements...)[variable(elements...)]...
DO NUM|UNNUM
DO [WHILE expression]
EDIT (* depends on variable BWB.EDITOR$)
ELSE
ELSEIF
END FUNCTION | IF | SELECT | SUB
ENVIRON variable-string$ = string$
ENVIRON$( variable-string )
EOF( device-number )
ERASE variable[, variable]...
ERL
ERR
ERROR number
EXIT FOR|DO
EXP( number )
FIELD [#] device-number, number AS string-variable [, number AS string-variable...]
FILES filespec$ (* depends on variable BWB.FILES$)
FOR counter = start TO finish [STEP increment]
FUNCTION function-definition
GET [#] device-number [, record-number]
GOSUB line | label
GOTO line | label
HEX$( number )
IF expression THEN [statement [ELSE statement]]
INKEY$
INPUT [# device-number]|[;]["prompt string";]list of variables
INSTR( [start-position,] string-searched$, string-pattern$ )
INT( number )
KILL file-name
LEFT$( string$, number-of-spaces )
LEN( string$ )
LET variable = expression
LINE INPUT [[#] device-number,]["prompt string";] string-variable$
LIST line[-line]
LOAD file-name
LOC( device-number )
LOCATE
LOF( device-number )
LOG( number )
LOOP [UNTIL expression]
LSET string-variable$ = expression
MERGE file-name
MID$( string$, start-position-in-string[, number-of-spaces ] )
MKD$( number )
MKDIR pathname
MKI$( number )
MKS$( number )
NAME old-file-name AS new-file-name
NEW
NEXT counter
OCT$( number )
ON variable GOTO|GOSUB line[,line,line,...]
ON ERROR GOSUB line | label
OPEN O|I|R, [#]device-number, file-name [,record length]
file-name FOR INPUT|OUTPUT|APPEND AS [#]device-number [LEN = record-length]
OPTION BASE number
POS
PRINT [# device-number,][USING format-string$;] expressions...
PUT [#] device-number [, record-number]
RANDOMIZE number
READ variable[, variable]...
REM string
RENUM
RESTORE line
RETURN
RIGHT$( string$, number-of-spaces )
RMDIR pathname
RND( number )
RSET string-variable$ = expression
RUN [line]|[file-name]
SAVE file-name
SELECT CASE expression
SGN( number )
SIN( number )
SPACE$( number )
SPC( number )
SQR( number )
STOP
STR$( number )
STRING$( number, ascii-value|string$ )
SUB subroutine-name
SWAP variable, variable
SYSTEM
TAB( number )
TAN( number )
TIME$
TIMER
TROFF
TRON
VAL( string$ )
WEND
WHILE expression
WIDTH [# device-number,] number
WRITE [# device-number,] element [, element ]....
