bwbasic的介绍，是一款Linux平台下的BASIC的解释器 Bywater BASIC Interpreter 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. 最近要移植一款basic解释器到arm开发板上，本来想移植yabasic的，下了yabaisc的源码包，发现其makefile文件写的太复杂了，都不知道从何改起。继续在ubuntu的新立得里搜索basic解释器，于是就搜到了今天的主角bwbasic。从网上下载到源码包，configure过后，发现makefile异常简洁，完全可以交叉编译，ok，go！ 1）首先下载bwbasic-2.20.tar.gz这个文件 2）解压后，在控制台该目录下运行./configure checking for gcc checking how to run the C preprocessor checking for install checking for size_t in sys/types.h checking for string.h checking for stdlib.h checking for unistd.h checking for raise creating config.status creating Makefile 3)修改Makefile 将CC = gcc改为CC = arm-linux-gcc 4)make,但有个错误 root@kyon-desktop:/4020/BASIC/bwbasic-2.20# make arm-linux-gcc -c -I. -DHAVE_STRING=1 -DHAVE_STDLIB=1 -DHAVE_UNISTD=1 -DHAVE_RAISE=1 -g -ansi bwbasic.c bwbasic.c:54: error: initializer element is not constant make: *** [bwbasic.o] 错误 1 5）修改bwbasic.c文件54行 FILE *errfdevice = stderr; 改为 FILE *errfdevice; 6）make通过 拷到ARM板子上试试吧,可以正确读取a.bas文件 VFS: Mounted root (nfs filesystem). Freeing init memory: 116K init started: BusyBox v1.9.2 (2008-08-15 10:15:54 CST) starting pid 15, tty '': '/etc/init.d/rcS' ******************************** SEU 4020 ARM Linux-2.6.16 ******************************** # mount all........... # Starting mdev......... starting pid 23, tty '': '/bin/sh' hwclock: settimeofday() failed: Invalid argument / # ls 1.txt demo mg-samples-1.3.1 sbin 1.txt~ dev mnt shell 2.txt espeak oos.c sys 2.txt~ etc oos.c~ test.wav a.bas home osstest tests a.bas~ i.mp3 plugins tmp bin lib proc usr bwbasic linuxrc root var bwbtest madplay.arm rt73.ko / # ./bwbasic Bywater BASIC Interpreter/Shell, version 2.20 Copyright (c) 1993, Ted A. Campbell bwBASIC: load "a.bas" bwBASIC: list : 20: print "hello,world!" 30: print "second" 40: end bwBASIC: run hello,world! second 附录：BWBASIC简单使用手册 ======================================================== Bywater BASICBywater BASIC fundamentals Introduction This document discusses fundamental operations of using Bywater BASIC on a Unix computer (such as cis.niagara.edu). Case sensitivity Bywater BASIC is case sensitive with respect to programmer-created identifiers such as variable names. This means, for example, that taxrate, taxRate, and TAXRATE are 3 distinct variable names. However, command and function names are not case sensitive. Thus, you may execute your program via run or RUN; you may compute the absolute value of the variable x via abs(x) or ABS(x). Getting into BASIC At the operating system prompt message, give the command bwbasic. Thus (with your typing underlined): cis $ bwbasic (Note: Unix commands are case sensitive - for example, BWBASIC won't work.) You should notice that the prompt message changes: the Bywater BASIC prompt message is bwBASIC: as opposed to the Unix prompt cis $ Retrieving a saved program file Use a command of the form load "programname". For example, if you have saved a program using the file name miles.bas, then you can retrieve this program as follows: bwBASIC: load "miles.bas" The quotation marks around the file name are required. Listing your program This refers to printing the list of statements that make up the program. You may list the entire program, or a single line, or a range of lines. Examples: bwBASIC: list 10: Rem a few lines of code to demo the behavior of the LIST command 20: rem Here's a jolly good line of code. 30: rem Here's a lousy line for attempting to start a relationship. Assume that the previous example shows the entire program used for the following examples. - - - - - - - - - - - - bwBASIC: list 10-20 10: Rem a few lines of code to demo the behavior of the LIST command 20: rem Here's a jolly good line of code. The above is an example of listing a range of lines, when the lines corresponding to the first and last linenumber in the range exist in the program. - - - - - - - - - - - - bwBASIC: list 10-15 10: Rem a few lines of code to demo the behavior of the LIST command 20: rem Here's a jolly good line of code. 30: rem Here's a lousy line for attempting to start a relationship. The above shows if you try to list a range, and the first linenumber of the range corresponds to an existing line of code but the last linenumber of the range does not, then the entire program is listed. Other dialects of BASIC would simply list all lines with linenumbers in the specified range. - - - - - - - - - - - - bwBASIC: list 10 10: Rem a few lines of code to demo the behavior of the LIST command The above is an example of trying to list one line, when the line requested exists in the program. - - - - - - - - - - - - bwBASIC: list 11 ERROR: Line number 11 not found Thus if you attempt to list one line using a non-existent linenumber, a message informs you that no such line exists. Entering a new line of code, or correcting an existing line Type the line (with its linenumber) as you wish it to appear in your program. Note when you list your program, Bwbasic will insert a colon following the linenumber. Lines of code are ordered by linenumber - if you enter lines out of order, they will automatically be sorted (using ascending order) according to their linenumbers. Since the linenumber must be an integer, it is wise to leave gaps in your numbering, so that you have the ability to insert additional lines of code if you decide it's desirable to do so. Removing an undesired line of code Just enter the linenumber of the undesired line to remove the line from your listing. For example, to remove line 15: bwBASIC: 15 Saving a program file Use a command of the form save "programname". For example, if you wish to save your current program using the file name blah.bas, use bwBASIC: save "blah.bas" The quotation marks around the file name are required. Running a program Running, or executing, a program, is the process of having the program do the work it's designed to do. This is done via the run command: bwBASIC: run Quitting BASIC Use the command quit - bwBASIC: quit This will return you to the operating system prompt message. Links Bywater BASIC - more info To Boxer's home page ……