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Newsgroups: comp.sources.misc From: tcamp@delphi.com (Ted A. Campbell) Subject: v40i052: bwbasic - Bywater BASIC interpreter version 2.10, Part01/15 Message-ID: <csm-v40i052=bwbasic.112142@sparky.Sterling.COM> X-Md4-Signature: 1ad90d355a4a15c007f2afe7e2595499 Sender: kent@sparky.sterling.com (Kent Landfield) Organization: Sterling Software Date: Fri, 29 Oct 1993 16:22:50 GMT Approved: kent@sparky.sterling.com Submitted-by: tcamp@delphi.com (Ted A. Campbell) Posting-number: Volume 40, Issue 52 Archive-name: bwbasic/part01 Environment: UNIX, DOS Supersedes: bwbasic: Volume 33, Issue 37-47 Bywater Software Announces Bywater BASIC Interpreter/Shell, version 2.10 --------------------------------------------- Copyright (c) 1993, Ted A. Campbell for bwBASIC version 2.10, 11 October 1993 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 (1.11): * now compilable on "stock" (older K&R specification) C compilers; * implements ANSI-BASIC-style structured programming, with called subroutines, multi-line functions, multi-line IF-THEN ELSE statements, SELECT CASE statements, etc.; * new enhancements to the interactive environment, such as DO NUM and DO UNNUM to number or unnumber all program lines; * addition of some hardware-specific commands such as CLS, LOCATE, and INKEY$ (at present for IBM PC and compatibles, using the Microsoft QuickC compiler), opening the way for more hardware- specific commands and functions in the future; * general improvements to reliability and portability, including more extensive testing than previous versions; COMMUNICATIONS: email: tcamp@delphi.com A LIST OF BASIC COMMANDS AND FUNCTIONS IMPLEMENTED in bwBASIC 2.10: 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$;] expressions... PUT [#] device-number [, record-number] RANDOMIZE number READ variable[, variable]... REM string RESTORE line RETURN RIGHT$( 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 ].... ----- #! /bin/sh # This is a shell archive. Remove anything before this line, then feed it # into a shell via "sh file" or similar. To overwrite existing files, # type "sh file -c". # Contents: bwbasic-2.10 bwbasic-2.10/INSTALL bwbasic-2.10/bwbasic.doc # bwbasic-2.10/bwbtest bwbasic-2.10/bwbtest/dataread.bas # Wrapped by kent@sparky on Thu Oct 21 10:47:47 1993 PATH=/bin:/usr/bin:/usr/ucb:/usr/local/bin:/usr/lbin ; export PATH echo If this archive is complete, you will see the following message: echo ' "shar: End of archive 1 (of 15)."' if test ! -d 'bwbasic-2.10' ; then echo shar: Creating directory \"'bwbasic-2.10'\" mkdir 'bwbasic-2.10' fi if test -f 'bwbasic-2.10/INSTALL' -a "${1}" != "-c" ; then echo shar: Will not clobber existing file \"'bwbasic-2.10/INSTALL'\" else echo shar: Extracting \"'bwbasic-2.10/INSTALL'\" $6264 characters$ sed "s/^X//" >'bwbasic-2.10/INSTALL' <<'END_OF_FILE' XSome Notes on Installation of the Bywater BASIC Interpreter: X----------------------------------------------------------- X X0. Quick-Start Guide For Compiling X X To use the default configuration (which is reasonable for most situations): X X On Unix, type "configure; make". X On MS-DOS using QuickC, type "nmake -f makefile.qcl". X X You can skip the rest of this file unless you want to customize the X BASIC dialect that is supported, or something goes wrong in the X above commands. X X1. Compiler Requirements X X Although earlier versions of bwBASIC would compile only with X ANSI C compilers, versions 2.10 and higher can be compiled X with "stock" C compilers, i.e., compilers that comply with X the older Kernighan and Ritchie C standard. X X Section I-B of bwbasic.h allows you to specify some compiler X features. If you have an ANSI C compiler, you needn't worry X with this. For stock C compilers, the default configuration X presumes that your compiler supports signal() and raise() X with the signal.h header, supports setjmp() and longjmp() X with the setjmp.h header, and has a separate string.h X header. If your compiler does not have these features X and the related header files, you can indicate this in X section I-B by setting appropriate flags to FALSE. X X X2. Configuration of header files X X You may need to examine file "bwbasic.h" to make important X changes for specific hardware and compiler configurations. X You may also need to change "bwx_tty.h" if you are using the X TTY implementation or "bwx_iqc.h" if you are using the version X for PCs with Microsoft QuickC (see below on "implementations"). X If you want to redefine messages or even the BASIC command X names, you will need to edit "bwb_mes.h". X X X3. Makefiles X X Several makefiles are provided: "makefile.qcl" will compile X the program utilizing the Microsoft QuickC (tm) line-oriented X compiler on DOS-based p.c.'s, and "makefile" will compile the X program on Unix-based computers utilizing either a stock C X compiler or Gnu C++. I have also compiled the program utilizing X Borland's Turbo C++ (tm) on DOS-based machines, although I have X not supplied a makefile for Turbo C++. X X If you try the "IQC" implementation, you will need to alter X makefile.qcl to include bwx_iqc.c (and bqx_iqc.obj) instead X of bwx_tty.*. X X X4. Implementations X X The present status of bwBASIC allows two major implementations X controlled by the IMP_TTY and IMP_IQC flags in bwbasic.h. X IMP_TTY is the base implementation and presumes a simple X TTY-style environment, with all keyboard and screen input X and output directed through stdin and stdout. If IMP_TTY is X defined as TRUE, then the file bwx_tty.h will be included, X and a makefile should include compilation of bwx_tty.c. X IMP_IQC is a somewhat more elaborate implementation for X the IBM PC and compatible microcomputers utilizing the X Microsoft QuickC compiler. This allows some more elaborate X commands (CLS and LOCATE) and the INKEY$ function, and X allows greater control over output. If IMP_IQC is defined X as TRUE in bwbasic.h, then bwx_iqc.h will be included and X bwx_iqc.c should be compiled in the makefile. X X Only one of the flags IMP_TTY or IMP_IQC should be set X to TRUE. X X X5. Flags Controlling Groups of Commands and Functions X X There are a number of flags which control groups of commands X and functions to be implemented. X X (core) Commands and Functions in any implementation of X bwBASIC; these are the ANSI Minimal BASIC core X X INTERACTIVE Commands supporting the interactive programming X environment X X COMMON_CMDS Commands beyond ANSI Minimal BASIC which are common X to Full ANSI BASIC and Microsoft BASICs X X COMMON_FUNCS Functions beyond the ANSI Mimimal BASIC core, but X common to both ANSI Full BASIC and Microsoft-style X BASIC varieties X X UNIX_CMDS Commands which require Unix-style directory and X environment routines not specified in ANSI C X X STRUCT_CMDS Commands related to structured programming; all X of these are part of the Full ANSI BASIC standard X X ANSI_FUNCS Functions unique to ANSI Full BASIC X X MS_CMDS Commands unique to Microsoft BASICs X X MS_FUNCS Functions unique to Microsoft BASICs X X X6. Configurations X X The file bwbasic.h includes a number of configuration options X that will automatically select groups of commands and functions X according to predetermined patterns. These are: X X CFG_ANSIMINIMAL Conforms to ANSI Minimal BASIC standard X3.60-1978. X X CFG_COMMON Small implementation with commands and functions X common to GWBASIC (tm) and ANSI full BASIC. X X CFG_MSTYPE Configuration similar to Microsoft line-oriented X BASICs. X X CFG_ANSIFULL Conforms to ANSI Full BASIC standard X3.113-1987 X (subset at present). X X CFG_CUSTOM Custom Configuration specified by user. X X Only one of these flags should be set to TRUE. X X X7. Adding Commands and Functions X X In order to add a new command to bwBASIC, follow the following X procedure: X X (a) Write the command body using function bwb_null() in bwb_cmd.c X as a template. The command-body function (in C) must receive a X pointer to a bwb_line structure, and must pass on a pointer to X a bwb_line structure. The preferred method for returning from X a command-body function is: return bwb_zline( l ); this will X discriminate between MULTISEG_LINES programs which advance to X the next segment and those which advance to the next line. X X (b) Add prototypes for the command-body function in bwbasic.h; X you'll need one prototype with arguments in the ANSI_C section X and one prototype without arguments in the non-ANSI_C section. X X (c) Add the command to the command table in bwb_tbl.c in the X group you have selected for it. X X (d) Increment the number of commands for the group in which X you have placed your command. X X The procedure for adding a new function is parallel to this, except that X you should use fnc_null() in bwb_fnc.c as the template, and the X function name must be added to the function table in bwb_tbl.c. END_OF_FILE if test 6264 -ne `wc -c <'bwbasic-2.10/INSTALL'`; then echo shar: \"'bwbasic-2.10/INSTALL'\" unpacked with wrong size! fi # end of 'bwbasic-2.10/INSTALL' fi if test -f 'bwbasic-2.10/bwbasic.doc' -a "${1}" != "-c" ; then echo shar: Will not clobber existing file \"'bwbasic-2.10/bwbasic.doc'\" else echo shar: Extracting \"'bwbasic-2.10/bwbasic.doc'\" $58924 characters$ sed "s/^X//" >'bwbasic-2.10/bwbasic.doc' <<'END_OF_FILE' X X X X X Bywater BASIC Interpreter/Shell, version 2.10 X --------------------------------------------- X X Copyright (c) 1993, Ted A. Campbell X for bwBASIC version 2.10, 11 October 1993 X X XCONTENTS: X X 1. DESCRIPTION X 2. TERMS OF USE X 3. QUICK REFERENCE LIST OF COMMANDS AND FUNCTIONS X 4. GENERAL NOTES ON USAGE X 5. EXPANDED REFERENCE FOR COMMANDS AND FUNCTIONS X 6. PREDEFINED VARIABLES X 7. UNIMPLEMENTED COMMANDS AND FUNCTIONS X and AGENDA FOR DEVELOPMENT X 8. THE STORY OF BYWATER BASIC X 9. COMMUNICATIONS X X The author wishes to express his thanks to Mr. David MacKenzie, X who assisted in the development Unix installation and configuration X for this version. X X X1. DESCRIPTION X X The Bywater BASIC Interpreter (bwBASIC) implements a large X superset of the ANSI Standard for Minimal BASIC (X3.60-1978) X and a significant subset of the ANSI Standard for Full BASIC X (X3.113-1987) in C. It also offers shell programming facilities X as an extension of BASIC. bwBASIC seeks to be as portable X as possible. X X bwBASIC can be configured to emulate features, commands, and X functions available on different types of BASIC interpreters; X see the file INSTALL for further installation information. X X The interpreter is fairly slow. Whenever faced with a choice X between conceptual clarity and speed, I have consistently chosen X the former. The interpreter is the simplest design available, X and utilizes no system of intermediate code, which would speed X up considerably its operation. As it is, each line is interpreted X afresh as the interpreter comes to it. X X bwBASIC implements one feature not available in previous BASIC X interpreters: a shell command can be entered interactively at the X bwBASIC prompt, and the interpreter will execute it under a X command shell. For instance, the command "dir *.bas" can be X entered in bwBASIC (under DOS, or "ls -l *.bas" under UNIX) and X it will be executed as from the operating system command line. X Shell commands can also be given on numbered lines in a bwBASIC X program, so that bwBASIC can be used as a shell programming X language. bwBASIC's implementation of the RMDIR, CHDIR, MKDIR, X NAME, KILL, ENVIRON, and ENVIRON$() commands and functions X offer further shell-processing capabilities. X X X2. TERMS OF USE: X X This version of Bywater BASIC is released under the terms of the X GNU General Public License (GPL), which is distributed with this X software in the file "COPYING". The GPL specifies the terms X under which users may copy and use the software in this distribution. X X A separate license is available for commercial distribution, X for information on which you should contact the author. X X X3. QUICK REFERENCE LIST OF COMMANDS AND FUNCTIONS X X Be aware that many of these commands and functions will not be X available unless you have set certain flags in the header files X (see the expanded reference section below for dependencies). X X ABS( number ) X ASC( string$ ) X ATN( number ) X CALL subroutine-name X CASE ELSE | IF partial-expression | constant X CHAIN [MERGE] file-name [, line-number] [, ALL] X CHDIR pathname X CHR$( number ) X CINT( number ) X CLEAR X CLOSE [[#]file-number]... X CLS X COMMON variable [, variable...] X COS( number ) X CSNG( number ) X CVD( string$ ) X CVI( string$ ) X CVS( string$ ) X DATA constant[,constant]... X DATE$ X DEF FNname(arg...)] = expression X DEFDBL letter[-letter](, letter[-letter])... X DEFINT letter[-letter](, letter[-letter])... X DEFSNG letter[-letter](, letter[-letter])... X DEFSTR letter[-letter](, letter[-letter])... X DELETE line[-line] X DIM variable(elements...)[variable(elements...)]... X DO NUM|UNNUM X DO [WHILE expression] X EDIT X ELSE X ELSEIF X END IF | FUNCTION | SELECT | SUB X ENVIRON variable-string = string X ENVIRON$( variable-string ) X EOF( device-number ) X ERASE variable[, variable]... X ERL X ERR X ERROR number X EXP( number ) X FIELD [#] device-number, number AS string-variable [, number AS string-variable...] X FILES filespec$ X FUNCTION X FOR counter = start TO finish [STEP increment] X GET [#] device-number [, record-number] X GOSUB line | label X GOTO line | label X HEX$( number ) X IF expression THEN [statement [ELSE statement]] X INKEY$ X INPUT [# device-number]|[;]["prompt string";]list of variables X INSTR( [start-position,] string-searched$, string-pattern$ ) X INT( number ) X KILL file-name X LEFT$( string$, number-of-spaces ) X LEN( string$ ) X LET variable = expression X LINE INPUT [[#] device-number,]["prompt string";] string-variable$ X LIST line[-line] X LOAD file-name X LOC( device-number ) X LOCATE line, column X LOF( device-number ) X LOG( number ) X LOOP [UNTIL expression] X LSET string-variable$ = expression X MERGE file-name X MID$( string$, start-position-in-string[, number-of-spaces ] ) X MKD$( number ) X MKDIR pathname X MKI$( number ) X MKS$( number ) X NAME old-file-name AS new-file-name X NEW X NEXT [counter] X OCT$( number ) X ON variable GOTO|GOSUB line[,line,line,...] X ON ERROR GOSUB line X OPEN "O"|"I"|"R", [#]device-number, file-name [,record length] X file-name FOR INPUT|OUTPUT|APPEND AS [#]device-number [LEN = record-length] X OPTION BASE number X POS X PRINT [# device-number,][USING format-string$;] expressions... X PUT [#] device-number [, record-number] X QUIT X RANDOMIZE number X READ variable[, variable]... X REM string X RESTORE line X RETURN X RIGHT$( string$, number-of-spaces ) X RMDIR pathname X RND( number ) X RSET string-variable$ = expression X RUN [line][file-name] X SAVE file-name X SELECT CASE expression X SGN( number ) X SIN( number ) X SPACE$( number ) X SPC( number ) X SQR( number ) X STOP X STR$( number ) X STRING$( number, ascii-value|string$ ) X SUB subroutine-name X SWAP variable, variable X SYSTEM X TAB( number ) X TAN( number ) X TIME$ X TIMER X TROFF X TRON X VAL( string$ ) X WEND X WHILE expression X WIDTH [# device-number,] number X WRITE [# device-number,] element [, element ].... X X X4. GENERAL NOTES ON USAGE: X X 4.a. Interactive Environment X X An interactive environment is provided if the flag INTERACTIVE X is defined as TRUE in bwbasic.h, so that a line with a X line number can be entered at the bwBASIC prompt and it will be X added to the program in memory. X X Line numbers are not strictly required, but are useful if the X interactive enviroment is used for programming. For longer X program entry one might prefer to use an ASCII text editor, and X in this case lines can be entered without numbers. One can use X DO NUM and DO UNNUM to number or unnumber lines. See also the X documentation below for the pseudo-command EDIT. X X 4.b. Naming Conventions X X Command names and function names are not case sensitive, X so that "Run" and "RUN" and "run" are equivalent and "abs()" X and "ABS()" and "Abs()" are equivalent. HOWEVER, variable X names ARE case sensitive in bwbASIC, so that "d$" and "D$" X are different variables. This differs from some BASIC X implementations where variable names are not case sensitive. X X Variable names can use any alphabetic characters, the period X and underscore characters and decimal digits (but not in the X first position). They can be terminated with '#' or '!' to X allow Microsoft-type names, even though the precision is X irrelevant to bwBASIC. X X 4.c. Numerical Constants X X Numerical constants may begin with a digit 0-9 (decimal), with X the "&H" or "&h" (hexadecimal) or the "&o" or "&O" (octal). X Decimal numbers may terminated with 'E', 'e', 'D', or 'd' X followed by an exponent number to denote exponential notation. X Decimal constants may also be terminated by the '#' or '!' X to comply with Microsoft-style precision terminators, although X the precision specified will be irrelevant to bwBASIC. X X 4.d. Command-Line Execution X X A filename can be specified on the command line and will be X LOADed and RUN immediately, so that the command line X X bwbasic prog.bas X X will load and execute "prog.bas". X X 4.e. Program Storage X X All programs are stored as ASCII text files. X X 4.f. TRUE and FALSE X X TRUE is defined as -1 and FALSE is defined as 0 in the default X distribution of bwBASIC. These definitions can be changed by X those compiling bwBASIC (see file BWBASIC.H). X X 4.g. Assignments X X Assignment must be made to variables. This differs from some X implementations of BASIC where assignment can be made to a X function. Implication: "INSTR( 3, x$, y$ ) = z$" will not X work under bwBASIC. X X 4.h. Operators and Precedence X X bwBASIC recognizes the following operators, with their level X of precedence given (1 = highest): X X ^ 1 exponentiation X * 2 multiplication X / 2 division X \ 3 integer division X + 5 addition X - 5 subtraction X = 6 equality or assignment X MOD 4 modulus (remainder) arithmetic X <> 7 inequality X < 8 less than X > 9 greater than X <= 10 less than or equal to X =< 10 less than or equal to X >= 11 greater than or equal to X => 11 greater than or equal to X NOT 12 negation X AND 13 conjunction X OR 14 disjunction X XOR 15 exclusive or X IMP 16 implication X EQV 17 equivalence X X 4.h. Numerical Precision (NOT) X X bwBASIC utilizes numbers with only one level of precision. If X the flag NUMBER_DOUBLE is defined as TRUE in bwbasic.h, the X precision implemented will be that of the C "double" data type; X otherwise (default) the precision will be that of the C "float" X type. At a number of points there are commands (or pseudo- X commands) that seem to recognize Microsoft-style precision X distinctions, but for the most part these are just work-around X aliases to allow Microsoft-style programs to be run. X X X5. EXPANDED REFERENCE FOR COMMANDS AND FUNCTIONS X X The "Dependencies" listed in the folowing reference materials X refers to flags that must be set to TRUE in bwbasic.h for the X associated command or function to be implemented. These flags X are as follows: X X (core) Commands and Functions in any implementation of X bwBASIC; these are the ANSI Minimal BASIC core X X INTERACTIVE Commands supporting the interactive programming X environment X X COMMON_CMDS Commands beyond ANSI Minimal BASIC which are common X to Full ANSI BASIC and Microsoft BASICs X X COMMON_FUNCS Functions beyond the ANSI Mimimal BASIC core, but X common to both ANSI Full BASIC and Microsoft-style X BASIC varieties X X UNIX_CMDS Commands which require Unix-style directory and X environment routines not specified in C X X STRUCT_CMDS Commands related to structured programming; all X of these are part of the Full ANSI BASIC standard X X ANSI_FUNCS Functions unique to ANSI Full BASIC X X MS_CMDS Commands unique to Microsoft BASICs X X MS_FUNCS Functions unique to Microsoft BASICs X X X ------------------------------------------ X X Function: ABS( number ) X X Description: ABS returns the absolute value of the argument 'number'. X X Dependencies: (core) X X ------------------------------------------ X X Function: ASC( string$ ) X X Description: ASC returns the ASCII code for the first letter in X the argument string$. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: ATN( number ) X X Description: ATN returns the arctangent value of the argument 'number' X in radians. X X Dependencies: (core) X X ------------------------------------------ X X Command: CALL subroutine-name X X Description: CALL calls a named subroutine (see SUB and END SUB). X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Command: CASE ELSE | IF partial-expression | constant X X Description: CASE introduces an element of a SELECT CASE statement X (see SELECT CASE). CASE IF introduces a conditional X SELECT CASE element, and CASE ELSE introduces a X default SELECT CASE element. X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Command: CHAIN [MERGE] file-name [, line-number] [, ALL] X X Description: CHAIN passes control to another BASIC program. X Variables declared COMMON (q.v.) will be passed X to the new program. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: CHDIR pathname$ X X Description: CHDIR changes the current directory to that indicated X by the argument pathname$. X X Dependencies: UNIX_CMDS X X ------------------------------------------ X X Function: CHR$( number ) X X Description: CHR$ returns a one-character string with the character X corresponding to the ASCII code indicated by argument X 'number'. X X Dependencies: COMMON_FUNCS X X ------------------------------------------ X X Function: CINT( number ) X X Description: CINT returns the truncated integer for the argument X 'number'. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: CLEAR X X Description: CLEAR sets all numerical variables to 0, and all X string variables to null. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: CLOSE [[#]file-number]... X X Description: CLOSE closes the file indicated by file-number X (see OPEN). X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: CLS X X Description: CLS clears the display screen (IBM and compatibles X only as of version 2.10). X X Dependencies: IMP_IQC and IMP_CMDLOC X X ------------------------------------------ X X Command: CMDS X X Description: CMDS is a debugging command that prints a list X of all implemented bwBASIC commands. X X Dependencies: DEBUG X X ------------------------------------------ X X Command: COMMON variable [, variable...] X X Description: COMMON designates variables to be passed to a CHAINed X program (see CHAIN). X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Function: COS( number ) X X Description: COS returns the cosine of the argument 'number' X in radians. X X Dependencies: (core) X X ------------------------------------------ X X Function: CSNG( number ) X X Description: CSNG is a pseudo-function that has no effect under X bwBASIC. It replicates a Microsoft-type command X that would convert the 'number' to single-precision. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: CVD( string$ ) X X Description: CVD converts the argument string$ into a bwBASIC X number (precision is irrelevant in bwBASIC since X bwBASIC numbers have only one precision). X X Implenentation-Specific Notes: X X CVD(), CVI(), CVS(), MKI$(), MKD$(), MKS$(): These functions X are implemented, but are dependent on a) the sizes for integer, X float, and double values on particular systems, and b) how X particular versions of C store these numerical values. The X implication is that data files created using these functions X on a DOS-based microcomputer may not be translated correctly X by bwBASIC running on a Unix-based computer. Similarly, data X files created by bwBASIC compiled by one version of C may not be X readable by bwBASIC compiled by another version of C (even under X the same operating system). So be careful with these. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: CVI( string$ ) X X Description: CVI converts the argument string$ into a bwBASIC X number (precision is irrelevant in bwBASIC since X bwBASIC numbers have only one precision; see also X the note on CVD). X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: CVS( string$ ) X X Description: CVI converts the argument string$ into a bwBASIC X number (precision is irrelevant in bwBASIC since X bwBASIC numbers have only one precision; see also X the note on CVD). X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: DATA constant[,constant]... X X Description: DATA stores numerical and string constants to be X accessed by READ (q.v.). X X Dependencies: (core) X X ------------------------------------------ X X Function: DATE$ X X Description: DATE$ returns the current date based on the computer's X internal clock as a string in the form "YYYY-MM-DD". X As implemented under bwBASIC, DATE$ cannot be used for X assignment (i.e., to set the system date). X X Note: bwBASIC presently (v2.10) does not allow assignment X to a function. X X Dependencies: COMMON_FUNCS X X ------------------------------------------ X X Command: DEF FNname(arg...)] = expression X X Description: DEF defines a user-written function. This function X corresponds to Microsoft-type implementation, although X in bwBASIC DEF is a working equivalent of FUNCTION. X X Dependencies: (core) X X ------------------------------------------ X X Command: DEFDBL letter[-letter](, letter[-letter])... X X Description: DEFDBL declares variables with single-letter names X as numerical variables (precision is irrelevant in X bwBASIC). X X Dependencies: MS_CMDS X X ------------------------------------------ X X Command: DEFINT letter[-letter](, letter[-letter])... X X Description: DEFINT declares variables with single-letter names X as numerical variables (precision is irrelevant in X bwBASIC). X X Dependencies: MS_CMDS X X ------------------------------------------ X X Command: DEFSNG letter[-letter](, letter[-letter])... X X Description: DEFSNG declares variables with single-letter names X as numerical variables (precision is irrelevant in X bwBASIC). X X Dependencies: MS_CMDS X X ------------------------------------------ X X Command: DEFSTR letter[-letter](, letter[-letter])... X X Description: DEFSTR declares variables with single-letter names X as string variables. X X Dependencies: MS_CMDS X X ------------------------------------------ X X Command: DELETE line[-line] X X Description: DELETE deletes program lines indicated by the X argument(s). If you want to use DELETE for non- X numbered programs, first use DO NUM, then DELETE, X then DO UNNUM. X X Dependencies: INTERACTIVE X X ------------------------------------------ X X Command: DIM variable(elements...)[variable(elements...)]... X X Description: DIM specifies variables that have more than one X element in a single dimension, i.e., arrayed X variables. X X Note: As implemented under bwBASIC, DIM accepts only X parentheses as delimiters for variable fields. X (Some BASICs allow the use of square brackets.) X X Dependencies: (core) X X ------------------------------------------ X X Command: DO NUM|UNNUM X X Description: DO NUM numbers all lines in a program. The first X line is given the number 10, and subsequent lines X are numbered consecutively in multiples of 10. DO X UNNUM removes all line numbers from a program. X NOTE that these functions do nothing to line X numbers, e.g., following a GOSUB or GOTO statement; X these commands cannot be used as a replacement for X RENUM (available in some systems, but not bwBASIC). X With these commands, however, one can develop X unnumbered programs by entering new lines with numbers, X then running DO UNNUM to remove the line numbers. X Together with LOAD and SAVE (q.v.) one can use X bwBASIC as a primitive text editor. X X Dependencies: INTERACTIVE X X ------------------------------------------ X X Command: DO [WHILE expression] X X Description: DO implements a number of forms of program loops. X DO...LOOP simply loops; the only way out is by X EXIT; DO WHILE...LOOP loops while "expression" is X true (this is equivalent to the older WHILE-WEND X loop, also implemented in bwBASIC); DO...LOOP UNTIL X loops until the expression following UNTIL is true. X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Command: EDIT X X Description: EDIT is a pseudo-command which calls the text editor X specified in the variable BWB.EDITOR$ to edit the X program in memory. After the call to the text editor, X the (edited) prgram is reloaded into memory. The user X normally must specific a valid path and filename in X BWB.EDITOR$ before this command will be useful. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: ELSE X X Description: ELSE introduces a default condition in a multi-line IF X statement. X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Command: ELSEIF X X Description: ELSEIF introduces a secondary condition in a multi- X line IF statement. X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Command: END IF | FUNCTION | SELECT | SUB X X Description: END IF ends a multi-line IF statement. END FUNCTION X ends a multi-line function definition. END SELECT X ends a SELECT CASE statement. END SUB ends a multi- X line subroutine definition. X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Command: ENVIRON variable-string$ = string$ X X Description: ENVIRON sets the environment variable identified by X variable-string$ to string$. X X It might be noted that this differs from the implementation X of ENVIRON in some versions of BASIC, but bwBASIC's ENVIRON X allows BASIC variables to be used on either side of the equals X sign. Note that the function ENVIRON$() is different from the X command, and be aware of the fact that in some operating systems X an environment variable set within a program will not be passed X to its parent shell. X X Dependencies: UNIX_CMDS X X ------------------------------------------ X X Function: ENVIRON$( variable-string$ ) X X Description: ENVIRON$ returns the environment variable associated with X the name variable-string$. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: EOF( device-number ) X X Description: EOF returns TRUE (-1) if the device associated with X device-number is at the end-of-file, otherwise it X returns FALSE (0). X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: ERASE variable[, variable]... X X Description: ERASE eliminates arrayed variables from a program. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Function: ERL X X Description: ERL returns the line number of the most recent error. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: ERR X X Description: ERR returns the error number of the most recent error. X X Note that if PROG_ERRORS has been defined when bwBASIC is X compiled, the ERR variable will not be set correctly upon X errors. It only works when standard error messages are used. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: ERROR number X X Description: ERROR simulates an error, i.e., displays the message X appropriate for that error. This command is helpful X in writing ON ERROR GOSUB routines that can identify X a few errors for special treatment and then ERROR ERR X (i.e., default handling) for all others. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: EXIT [FOR] X X Description: EXIT by itself exits from a DO...LOOP loop; X EXIT FOR exits from a FOR...NEXT loop. X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Function: EXP( number ) X X Description: EXP returns the exponential value of 'number'. X X Dependencies: (core) X X ------------------------------------------ X X Command: FIELD [#] device-number, number AS string-variable$ [, number AS string-variable$...] X X Description: FIELD allocates space in a random file buffer for device X indicated by device-number, allocating 'number' bytes X and assigning the bytes at this position to the variable X string-variable$. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: FILES filespec$ X X Description: FILES is a pseudocommand that invokes the directory program X specified in the variable BWB.FILES$ with the argument X filespec$. Normally, the user must set this variable X before FILES can be used. E.g., for PC-type computers, X X BWB.FILES$ = "DIR" X X will work, for Unix machines, X X BWB.FILES$ = "ls -l" X X etc. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: FNCS X X Description: CMDS is a debugging command that prints a list X of all pre-defined bwBASIC functions. X X Dependencies: DEBUG X X ------------------------------------------ X X Command: FUNCTION X X Description: FUNCTION introduces a function definition, normally X ending with END FUNCTION. In bwBASIC, FUNCTION and X DEF are qorking equivalents, so either can be used X with single-line function definitions or with multi- X line definitions terminated by END FUNCTION. X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Command: FOR counter = start TO finish [STEP increment] X X Description: FOR initiates a FOR-NEXT loop with the variable X 'counter' initially set to 'start' and incrementing X in 'increment' steps (default is 1) until 'counter' X equals 'finish'. X X Dependencies: (core) X X ------------------------------------------ X X Command: GET [#] device-number [, record-number] X X Description: GET reads the next reacord from a random-access file X or device into the buffer associated with that file. X If record-number is specified, the GET command reads the X specified record. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: GOSUB line | label X X Description: GOSUB initiates a subroutine call to the line (or label) X specified. The subroutine must end with RETURN. X X Dependencies: (core), but STRUCT_CMDS for labels X X ------------------------------------------ X X Command: GOTO line | label X X Description: GOTO branches program execution to the specified line X (or label). X X Dependencies: (core), but STRUCT_CMDS for labels X X ------------------------------------------ X X Function: HEX$( number ) X X Description: HEX$ returns a string giving the hexadecimal (base 16) X value for the 'number'. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: IF expression THEN [statement [ELSE statement]] X X Description: IF evaluates 'expression' and performs the THEN X statement if it is true or (optionally) the X ELSE statement if it is FALSE. If STRUCT_CMDS X is set to TRUE, bwBASIC allows multi-line IF X statements with ELSE and ELSEIF cases, ending X with END IF. X X Dependencies: (core), STRUCT_CMDS for multi-line IF statements X X ------------------------------------------ X X Function: INKEY$ X X Description: INKEY$ reads the status of the keyboard, and a single X keypress, if available. If a keypress is not available, X then INKEY$ immediately returns a null string (""). X Currently (v2.10) implemented in bwx_iqc.c only. X X Dependencies: IMP_IQC and IMP_CMDLOC X X ------------------------------------------ X X Command: INPUT [# device-number]|[;]["prompt string";]list of variables X X Description: INPUT allows input from the terminal or a device X specified by device-number. If terminal, the "prompt X string" is output, and input is assigned to the X appropriate variables specified. X X bwBASIC does not support the optional feature of INPUT X that suppresses the carriage-return and line-feed at the end X of the input. This is because C alone does not provide for any X means of input other than CR-LF-terminated strings. X X Dependencies: (core) X X ------------------------------------------ X X Function: INSTR( [start-position,] string-searched$, string-pattern$ ) X X Description: INSTR returns the position at which string-pattern$ X occurs in string-searched$, beginning at start-position. X As implemented in bwBASIC, INSTR cannot be used for X assignments. X X Note: bwBASIC presently (v2.10) does not allow assignment X to a function. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: INT( number ) X X Description: INT returns the largest integer less than or equal to X the argument 'number'. NOTE that this is not a "truncated" X integer function, for which see CINT. X X Dependencies: (core) X X ------------------------------------------ X X Command: KILL file-name$ X X Description: KILL deletes the file specified by file-name$. X X Dependencies: UNIX_CMDS X X ------------------------------------------ X X Function: LEFT$( string$, number-of-spaces ) X X Description: LEFT$ returns a substring a string$ with number-of-spaces X from the left (beginning) of the string). As implemented X under bwBASIC, it cannot be used for assignment. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: LEN( string$ ) X X Description: LEN returns the length in bytes of string$. X X Dependencies: COMMON_FUNCS X X ------------------------------------------ X X Command: LET variable = expression X X Description: LET assigns the value of 'expression' to the variable. X As currently implemented, bwBASIC supports implied LET X statements (e.g., "X = 4.5678" at the beginning of X a line or line segment, but does not support assignment X to multiple variables (e.g., "x, y, z = 3.141596"). X X Dependencies: (core) X X ------------------------------------------ X X Command: LINE INPUT [[#] device-number,]["prompt string";] string-variable$ X X Description: LINE INPUT reads entire line from the keyboard or a file X or device into string-variable$. If input is from the X keyboard (stdin), then "prompt string" will be printed X first. Unlike INPUT, LINE INPUT reads a whole line, X not stopping for comma-delimited data items. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: LIST line[-line] X X Description: LIST lists program lines as specified in its argument. X X Dependencies: INTERACTIVE X X ------------------------------------------ X X Command: LOAD file-name X X Description: LOAD loads an ASCII BASIC program into memory. X X Dependencies: INTERACTIVE X X ------------------------------------------ X X Function: LOC( device-number ) X X Description: LOC returns the next record that GET or PUT statements X will use. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: LOCATE line, column X X Description: LOCATE addresses trhe curor to a specified line and X column. Currently (v2.10) implemented in bwx_iqc.c only. X X Dependencies: IMP_IQC and IMP_CMDLOC X X ------------------------------------------ X X Function: LOF( device-number ) X X Description: LOF returns the length of a file (specified by device-number) X in bytes. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: LOG( number ) X X Description: LOG returns the natural logarithm of the argument 'number'. X X Dependencies: (core) X X ------------------------------------------ X X Command: LOOP [UNTIL expression] X X Description: LOOP terminates a program loop: see DO. X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Command: LSET string-variable$ = expression X X Description: LSET transfers data from 'expression' to the left-hand X side of a string variable or random access buffer field. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: MERGE file-name X X Description: MERGE adds program lines from 'file-name' to the program X in memory. Unlike LOAD, it does not clear the program X currently in memory. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Function: MID$( string$, start-position-in-string[, number-of-spaces ] ) X X Description: MID$ returns a substring of string$ beginning at X start-position-in-string and continuing for X number-of-spaces bytes. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: MKDIR pathname$ X X Description: MKDIR creates a new directory path as specified by X pathname$. X X Dependencies: UNIX_CMDS X X ------------------------------------------ X X Function: MKD$( number ) X X Description: MKD$, MKI$, and MKS$ are all equivalent in bwBASIC. X They convert the numerical value 'number' into a string X which can be stored in a more compressed form in a file X (especially for random file access). Since bwBASIC does X not recognize differences in precision, these commands X are effectively equivalent. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: MKI$( number ) X X Description: Equivalent to MKD$ (q.v.) X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: MKS$( number ) X X Description: Equivalent to MKD$ (q.v.). X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: NAME old-file-name AS new-file-name X X Description: NAME renames an existing file (old-file-name) as X new-file-name. X X Dependencies: UNIX_CMDS X X ------------------------------------------ X X Command: NEW X X Description: NEW deletes the program in memory and clears all X variables. X X Dependencies: INTERACTIVE X X ------------------------------------------ X X Command: NEXT [counter-variable] X X Description: NEXT comes at the end of a FOR-NEXT loop; see FOR. X X Dependencies: (core) X X ------------------------------------------ X X Function: OCT$( number ) X X Description: OCT$ returns a string giving the octal (base 8) X representation of 'number'. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: ON variable GOTO|GOSUB line[,line,line,...] X X Description: ON either branches (GOTO) or calls a subroutine X (GOSUB) based on the rounded value of variable; X if it is 1, the first line is called, if 2, the second X line is called, etc. X X Dependencies: (core) X X ------------------------------------------ X X Command: ON ERROR GOSUB line|label X X Description: ON ERROR sets up an error handling subroutine. See X also ERROR. X X Dependencies: COMMON_CMDS, STRUCT_CMDS for labels X X ------------------------------------------ X X Command: OPEN "O"|"I"|"R", [#]device-number, file-name [,record length] X file-name FOR INPUT|OUTPUT|APPEND AS [#]device-number [LEN = record-length] X X Description: OPEN allocates random access memory for access to a disk X file or other device. Note that two quite different forms X of the OPEN statement are supported. In the first form, X "O" (note that these letters must be encased in quotation X marks) denotes sequential output, "I" denotes sequential X input, and "R" denotes random-access input and output. X Once OPEN, any number of operations can be performed X on a device (see WRITE #, INPUT #, PRINT #, etc.). X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: OPTION BASE number X X Description: OPTION BASE sets the lowest value for array subscripts, X either 0 or 1. X X Dependencies: (core) X X ------------------------------------------ X X Function: POS X X Description: POS returns the current cursor position in the line. X X Dependencies: COMMON_FUNCS X X ------------------------------------------ X X Command: PRINT [# device-number,][USING format-string$;] expressions... X X Description: PRINT outputs text to the screen or to a file or device X specified by device-number. In the current implementation X of bwBASIC, expressions to be printed must be separated by X the comma (tabbed output), the semicolon (immediate X sequential output) or the plus sign (immediate sequential X output by string concatenation). Expressions separated X by blanks or tabs are not supported. If USING is specified, X a number of formatting marks may appear in the format X string: X X ! prints the first character of a string X X \\ prints 2+x characters of a string, where x = X the number of spaces between the backslashes X X & variable-length string field X X # represents a single digit in output format for X a number X X . decimal point in a number X X + sign of a number (will output + or -) X X - trailing minus after a number X X ** fill leading spaces with asterisks X X $$ output dollar sign in front of a number X X ^^ output number in exponential format X X _ output next character literally X X As currently implemented, the exponential format X will be that used by the C compiler. X X Dependencies: (core), COMMON_FUNCS for USING X X ------------------------------------------ X X Command: PUT [#] device-number [, record-number] X X Description: PUT outputs the next available record or the record X specified by record-number to the file or device X denoted by device-number. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: QUIT X X Description: QUIT is a synonym for SYSTEM; with INTERACTIVE X environment, it exits the program to the X operating system (or the calling program). X X Dependencies: INTERACTIVE X X ------------------------------------------ X X Command: RANDOMIZE number X X Description: RANDOMIZE seeds the random number generator (see RND). X Under bwBASIC, the TIMER function (q.v.) can be used X to supply a 'number' seed for the random number X generator. X X Dependencies: (core) X X ------------------------------------------ X X Command: READ variable[, variable]... X X Description: READ reads values from DATA statements and assigns these X values to the named variables. Variable types in a READ X statement must match the data types in DATA statements X as they are occurred. See also DATA and RESTORE. X X Dependencies: (core) X X ------------------------------------------ X X Command: REM string X X Description: REM allows remarks to be included in a program. As X currently implemented, the entire line following X REM is ignored by the interpreter (thus, even if X MULTISEG_LINES is set, a REM line will not be able X to find a segment delimiter (":") followed by another X line segment with command. bwBASIC does not currently X implement the Microsoft-style use of the single quotation X mark to denote remarks. X X Dependencies: (core) X X ------------------------------------------ X X Command: RESTORE line X X Description: RESTORE resets the line and position counters for DATA X and READ statements to the top of the program file or X to the beginning of the specified line. (Currently this X must be a line number.) X X Dependencies: (core) X X ------------------------------------------ X X Command: RETURN X X Description: RETURN concludes a subroutine called by GOSUB. X X Dependencies: (core) X X ------------------------------------------ X X Function: RIGHT$( string$, number-of-spaces ) X X Description: RIGHT$ returns a substring a string$ with number-of-spaces X from the right (end) of the string). As implemented X under bwBASIC, it cannot be used for assignment. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: RMDIR pathname X X Description: RMDIR deletes the directory path indicated by pathname. X X Dependencies: UNIX_CMDS X X ------------------------------------------ X X Function: RND( number ) X X Description: RND returns a pseudo-random number. The 'number' value X is ignored by bwBASIC if supplied. The RANDOMIZE X command (q.v.) reseeds the random-number generator. X X Dependencies: (core) X X ------------------------------------------ X X Command: RSET string-variable$ = expression X X Description: RSET transfers data from 'expression' to the right-hand X side of a string variable or random access buffer field. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: RUN [line][file-name$] X X Description: RUN executes the program in memory. If a file-name$ is X supplied, then the specified file is loaded into memory X and executed. If a line number is supplied, then execution X begins at that line. X X Dependencies: INTERACTIVE X X ------------------------------------------ X X Command: SAVE file-name$ X X Description: SAVE saves the program in memory to file-name$. bwBASIC X only saves files in ASCII format. X X Dependencies: INTERACTIVE X X ------------------------------------------ X X Command: SELECT CASE expression X X Description: SELECT CASE introduces a multi-line conditional selection X statement. The expression given as the argument to SELECT X CASE will be evaluated by CASE statements following. The X SELECT CASE statement conclludes with an END SELECT X statement. X X As currently implemented, CASE statements may be followed X by string values, but in this case only simple comparisons X (equals, not equals) can be performed. X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Function: SGN( number ) X X Description: SGN returns the sign of the argument 'number', +1 X for positive numbers, 0 for 0, and -1 for negative numbers. X X Dependencies: (core) X X ------------------------------------------ X X Function: SIN( number ) X X Description: SIN returns the sine of the argument 'number' X in radians. X X Dependencies: (core) X X ------------------------------------------ X X Function: SPACE$( number ) X X Description: SPACE$ returns a string of blank spaces 'number' X bytes long. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: SPC( number ) X X Description: SPC returns a string of blank spaces 'number' X bytes long. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Function: SQR( number ) X X Description: SQR returns the square root of the argument 'number'. X X Dependencies: (core) X X ------------------------------------------ X X Command: STOP X X Description: STOP interrupts program execution. As implemented under X bwBASIC, STOP issues a SIGINT signal. X X Dependencies: (core) X X ------------------------------------------ X X Function: STR$( number ) X X Description: STR$ returns a string giving the decimal (base 10) X representation of the argument 'number'. X X Dependencies: COMMON_FUNCS X X ------------------------------------------ X X Function: STRING$( number, ascii-value|string$ ) X X Description: STRING$ returns a string 'number' bytes long consisting X of either the first character of string$ or the character X answering to the ASCII value ascii-value. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: SUB subroutine-name X X Description: SUB introduces a named, multi-line subroutine. The X subroutine is called by a CALL statement, and concludes X with an END SUB statement. X X Dependencies: STRUCT_CMDS X X ------------------------------------------ X X Command: SWAP variable, variable X X Description: SWAP swaps the values of two variables. The two variables X must be of the same type (either numerical or string). X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: SYSTEM X X Description: SYSTEM exits from bwBASIC to the calling program or X (more usually) the operating system. X X Dependencies: INTERACTIVE X X ------------------------------------------ X X Function: TAB( number ) X X Description: TAB outputs spaces until the column indicated by X 'number' has been reached. X X Dependencies: (core) X X ------------------------------------------ X X Function: TAN( number ) X X Description: TAN returns the tangent of the argument 'number' X in radians. X X Dependencies: (core) X X ------------------------------------------ X X Function: TIME$ X X Description: TIME$ returns the current time based on the computer's X internal clock as a string in the form "HH-MM-SS". X As implemented under bwBASIC, TIME$ cannot be used for X assignment (i.e., to set the system time). X X Note: bwBASIC presently (v2.10) does not allow assignment X to a function. X X Dependencies: COMMON_FUNCS X X ------------------------------------------ X X Function: TIMER X X Description: TIMER returns the time in the system clock in seconds X elapsed since midnight. X X Dependencies: MS_FUNCS X X ------------------------------------------ X X Command: TROFF X X Description: TROFF turns of the trace facility; see TRON. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: TRON X X Description: TRON turns on the trace facility. This facility will print X each line number in square brackets as the program is X executed. This is useful in debugging programs with X line numbers. To debug an unnumbered program with X TRON, call DO NUM first, but remember to call DO UNNUM X before you save the program later. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Function: VAL( string$ ) X X Description: VAL returns the numerical value of the string$. X X Dependencies: COMMON_FUNCS X X ------------------------------------------ X X Command: VARS X X Description: VARS is a debugging command which prints a list of X all variables defined which have global scope. X X Dependencies: DEBUG X X ------------------------------------------ X X Command: WEND X X Description: WEND concludes a WHILE-WEND loop; see WHILE. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: WHILE expression X X Description: WHILE initiates a WHILE-WEND loop. The loop ends with X WEND, and execution reiterates through the loop as X long as the 'expression' is TRUE (-1). X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: WIDTH [# device-number,] number X X Description: WIDTH sets screen or device output to 'number' X columns. device-number specifies the device X or file for oputput. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X Command: WRITE [# device-number,] element [, element ].... X X Description: WRITE outputs variables to the screen or to a file X or device specified by device-number. Commas X are inserted between expressions output, and strings X are enclosed in quotation marks. X X Dependencies: COMMON_CMDS X X ------------------------------------------ X X X6. PREDEFINED VARIABLES X X BWB.EDITOR$ X BWB.FILES$ X BWB.PROMPT$ X BWB.IMPLEMENTATION$ X X The commands EDIT and FILES are pseudo-commands that launch X shell programs named in the variables BWB.EDITOR$ and BWB.FILES$, X respectively. The default values for these variables can X be changed in bwbasic.h (DEF_EDITOR and DEF_FILES), or they X can be changed on the fly by the user. An idea might be to X initialize these variables in "profile.bas" for specific X implementations; for instance, BWB.FILES$ might be defined as X "ls -l" on Unix systems or "dir" on DOS systems. X X The preset variable BWB.PROMPT$ can be used to set the prompt X string for bwBASIC. Again, it is suggested that a user- X selected promptcan be set up in a "profile.bas" to be X initialized each time bwBASIC starts. Note that special X characters can be added to the prompt string, e.g., X X BWB.PROMPT$ = "Ok"+CHR$(10) X X will give an "Ok" prompt followed by a linefeed. X X The preset variable BWB.IMPLEMENTATION$ will return "TTY" for X the bwx_tty implementation and will return "IQC" for the X IBM PC or Compatibles with QuickC (bwx_iqc) implementation. X This may be useful in determing which commands and functions X (specifically CLS, LOCATE, and INKEY$) may be available. X X X7. UNIMPLEMENTED COMMANDS AND FUNCTIONS, and AGENDA FOR DEVELOPMENT X X There are some items not implemented that have been so long X a part of standard BASICs that their absence will seem surprising. X In each case, though, their implementation would require opera- X ting-system-specific functions or terminal-specific functions X that cannot be universally provided. Some specific examples: X X CLOAD Relies on CP/M or MSDOS conventions for binary X executable files. X X CONT See RESUME below (programmer ignorance?). X X DEF USR Relies on CP/M or MSDOS conventions for binary X executable files. X X FRE() The ability to report the amount of free memory X remaining is system-specific due to varying patterns X of memory allocation and access; consequently this X ability is not present in ANSI or earlier versions X of C and this function is not available in bwBASIC. X X INPUT$() C by itself is not able to read unechoed keyboard X input, and can read keyboard input only after a X Carriage-Return has been entered. X X INP Calls to hardware ports, like machine-language X routines, are highly system-specific and cannot X be implemented in C alone. X X LLIST See LPRINT below. X X LPOS See LPRINT below. X X LPRINT and LLIST, etc., require access to a printer device, X and this varies from one system to another. Users X might try OPENing the printer device on their own X operating system (e.g., "/dev/lp" on Unix systems, X or "PRN" under DOS) and see if printing can be done X from bwBASIC in this way. X X NULL In this case, I am convinced that NULL is no longer X necessary, since very few printers now require NULLs X at the end of lines. X X OUT See INP above (calls to hardware ports). X X PEEK() PEEK and POKE enabled earlier BASICs to address X particular memory locations. Although bwBASIC X could possibly implement this command (POKE) and X this function (PEEK()), the limitation would be X highly limited by the different systems for X memory access in different systems. X X POKE see PEEK() above. X X RENUM Since unnumbered lines can be entered and X executed under bwBASIC, it would not be X possible to implement a RENUM routine. X Instead, bwBASIC uses DO NUM and DO UNNUM. X X RESUME Is this possible under C? If so, I X simply have failed to figure it out yet. X Mea culpa (but not maxima). X X USR See CALL and DEF USR above (machine language X subroutines). X X VARPTR See PEEK and POKE above. X X WAIT See INP and OUT above. X X There are other commands, functions, and implementation details X that I am working on, and which are on the agenda list for future X versions of bwBASIC. These agenda include: X X PARACT i.e., the ability to execute PARallel ACTions. This X is described in ANSI BASIC, although I have not seen it X implemented before. It will offer a rough, non- X preemptive form of multitasking within the scope X of a BASIC program. Programmers will note points at which X there are already hooks for PARACT in bwBASIC. X X XMEM PC-type computers need to be able to use extended X memory. If we could use extended memory for program X lines, variables, and function defitions, we could X write much longer programs. This would entail, X however, a fairly serious rewriting of the program X to utilize memory handles for these storage features X instead of direct memory pointers. X X Windows The addition of memory handles in addition to the X non-preemptive execution of program lines (in a X crude form, already present) will make it possible X to develop implementations for Windows and perhaps X for other graphical user interfaces. But what form X should this take? I have in mind presently a BASIC X that would run in the background, appearing only X as an icon in the GUI space, with pop-up editors X and output windows. Thus, the interpreted language X would serve a purpose something like 'cron' (a task X scheduler) under Unix systems. You may have some X reflections that would help me in this. X X Graphics Here we face fairly critical differences in different X styles and implementations of graphics, e.g., between X GWBASIC, ANSI BASIC, VisualBASIC, etc. But it's X possible that Graphics commands and functions could X be added. These would all be implementation-specific. X X The ANSI Standard for full BASIC does not specify which particular X commands or functions must be implemented, and in fact the standard X is very robust. Perhaps no implementation of BASIC would ever X include all of the items, but some ANSI commands and functions which X remain unimplemented are: X X ACCESS X ANGLE X AREA X ARITHMETIC X ARRAY X ASK X BSTR X BVAL X CEIL X CELLS X CLIP X COLLATE X CONNECT X COSH X DATUM X DEBUG X DECIMAL X DECLARE X DEGREES X DEVICE X DISCONNECT X DISPLAY X DOT X DRAW X ERASE X EVENT X EXCEPTION X GRAPH X HANDLER X IMAGE X KEY X LCASE X LINES X LOG10 X LOG2 X MAT X MIX X MULTIPOINT X OUTIN X OUTPUT X PARACT X PICTURE X PIXEL X PLOT X POINTS X RADIANS X RECEIVE X RENUMBER X REWRITE X ROTATE X ROUND X SEIZE X SEND X SHIFT X SINH X TANH X TIMEOUT X TRACE X TRANSFORM X TRUNCATE X UBOUND X UCASE X VIEWPORT X WAIT X VIEWPORT X ZONEWIDTH X X X8. THE STORY OF BYWATER BASIC X X This program was originally begun in 1982 by my grandmother, Mrs. X Verda Spell of Beaumont, TX. She was writing the program using X an ANSI C compiler on an Osborne I CP/M computer and although my X grandfather (Lockwood Spell) had bought an IBM PC with 256k of X RAM my grandmother would not use it, paraphrasing George Herbert X to the effect that "He who cannot in 64k program, cannot in 512k." X She had used Microsoft BASIC and although she had nothing against X it she said repeatedly that she didn't understand why Digital X Research didn't "sue the socks off of Microsoft" for version 1.0 X of MSDOS and so I reckon that she hoped to undercut Microsoft's X entire market and eventually build a new software empire on X the North End of Beaumont. Her programming efforts were cut X tragically short when she was thrown from a Beaumont to Port X Arthur commuter train in the summer of 1986. I found the source X code to bwBASIC on a single-density Osborne diskette in her knitting X bag and eventually managed to have it all copied over to a PC X diskette. I have revised it slightly prior to this release. You X should know, though, that I myself am an historian, not a programmer. X X X9. COMMUNICATIONS: X X email: tcamp@delphi.com X END_OF_FILE if test 58924 -ne `wc -c <'bwbasic-2.10/bwbasic.doc'`; then echo shar: \"'bwbasic-2.10/bwbasic.doc'\" unpacked with wrong size! fi # end of 'bwbasic-2.10/bwbasic.doc' fi if test ! -d 'bwbasic-2.10/bwbtest' ; then echo shar: Creating directory \"'bwbasic-2.10/bwbtest'\" mkdir 'bwbasic-2.10/bwbtest' fi if test -f 'bwbasic-2.10/bwbtest/dataread.bas' -a "${1}" != "-c" ; then echo shar: Will not clobber existing file \"'bwbasic-2.10/bwbtest/dataread.bas'\" else echo shar: Extracting \"'bwbasic-2.10/bwbtest/dataread.bas'\" $505 characters$ sed "s/^X//" >'bwbasic-2.10/bwbtest/dataread.bas' <<'END_OF_FILE' X10 rem DATAREAD.BAS -- Test DATA, READ, and RESTORE Statements X20 print "DATAREAD.BAS -- Test DATA, READ, and RESTORE Statements" X30 DATA "Ted", 56.789 X40 REM just to see if it advances correctly X50 DATA "Dale", 45.678 X 60 READ N$, NUMBER, ANOTHER$ X 70 READ ANUMBER X 80 PRINT "Data read: ";N$;" ";NUMBER;" ";ANOTHER$;" ";ANUMBER X90 RESTORE 30 X 100 READ ANOTHER$ X 110 READ ANUMBER, N$,NUMBER X 120 PRINT "After RESTORE:" X 130 PRINT "Data read: ";ANOTHER$;" ";ANUMBER;" ";N$;" ";NUMBER X140 END END_OF_FILE if test 505 -ne `wc -c <'bwbasic-2.10/bwbtest/dataread.bas'`; then echo shar: \"'bwbasic-2.10/bwbtest/dataread.bas'\" unpacked with wrong size! fi # end of 'bwbasic-2.10/bwbtest/dataread.bas' fi echo shar: End of archive 1 $of 15$. cp /dev/null ark1isdone MISSING="" for I in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ; do if test ! -f ark${I}isdone ; then MISSING="${MISSING} ${I}" fi done if test "${MISSING}" = "" ; then echo You have unpacked all 15 archives. rm -f ark[1-9]isdone ark[1-9][0-9]isdone else echo You still must unpack the following archives: echo " " ${MISSING} fi exit 0 exit 0 # Just in case...