System Snoop
Volume Number: | | 4
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Issue Number: | | 11
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Column Tag: | | Basic School
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System Snooping in MS QuickBasic
By Dave Kelly, MacTutor Editorial Board
MS QuickBasic Arrives!!
Its been a long wait (nearly a year and a half) but Microsoft has finally upgraded their infamous compiler. The best part is that it has really improved!! Microsoft took their interpreter which has always been an excellent product, and combined their compiler to produce what they are calling a new product named QuickBASIC 1.0.
There are some major changes that have taken place and many things have remained the same. The programming environment includes the same pretty-printing editor (with some improvements) which was included in earlier versions of the interpreter. There are still two versions of basic, the binary version and decimal version. Programs written using earlier versions of MS BASIC still function properly and in some cases they even work better. When you start listing all of the changes you can easily see why Microsoft chose to call it version 1.0 instead of MS Compiler version 2.0.
The first obvious change is the manual. MS QuickBASIC is now packaged as a shrink wrapped book and disk like their competitors. Most of the fancy packaging on software goes in the trash most of the time anyway. If removing the expense of the packaging lowers the price like it did for this one, I vote that all software companies do the same on all their software. QuickBASIC is priced at a mere $99!! Registered users of either MS Basic Interpreter or Compiler may upgrade to MS QuickBASIC 1.0 for $40. Upgrades are free to any registered user who acquired either of Microsofts BASIC products for the Macintosh after August 1, 1988. MS QuickBASIC now requires at least 1 MB of memory. The new manual includes two books in one. The users guide includes a description of how to use the interpreter/compiler functions, a tutorial on developing programs using QuickBASIC, a tutorial on debugging your program, creating a stand-alone application, documentation on how to access the Macintosh toolbox, and documentation for ResEdit (an older version is included with QuickBASIC) and Edit (QuickBASIC includes the latest version of the MDS editor which bombs on the Mac II). The second part of the manual is the BASIC Language Reference which includes a description of Basic variables, syntax, a statement and function reference, and appendix. The appendix contains documentation for invoking ROM routines and the Toolbox library, also some very good information about creating your own Libraries (similar to the old BMLL document) including how to write your own routines from Assembly, C or Pascal. Instructions are also given to install your own icon after compiling your stand-alone application.
The menu bar has now changed. As a matter of fact, when programs are run, a default menu is used which includes File and Edit menus. QuickBASIC removes its own menus so you no longer have to clear the menus when running your program as in earlier versions. Using the compiler options, you may disable the default menu and window for compiled programs.
The Search menu contains new menu items, Get Info and Set Info which allows the user to add new items into the Help data base, or add comments to the help that already exists. The text added is stored in the BASIC source code itself so Help can be different for different programs. It is not known if the Help text can be moved from one source code file to another. The Set Info item cannot be found in the manual and in some respects does not seem to work properly. Once it even corrupted the default help info which is stored in the QuickBASIC application. It is handy to type cmd-I (Get Info) while editing and get a dialog explaining the command that the cursor is pointing to. Another nice feature is the bookmarks. You can set a bookmark to force BASIC to remember the page that you are on so you can return there quickly.
The interpreter is able to help debug your program. For example, before executing the program, breakpoints may be set by inserting a stop sign icon. When the program stops at a breakpoint, or encounters an error, the value of key variables may be displayed. (This smells like Lightspeed doesnt it?) You may then change the value of any variables and continue execution. The highlighted tracing option which was available in earlier versions of MS Basic is still available in QuickBASIC too.
Figure 1. Example Listing
One of the most needed enhancements was HFS support. Now, MS Basic is smart enough to find files anywhere. If you have a LIBRARY statement you dont have to include the full path name because the first time your program is run, if QuickBASIC cant find your library file, it asks you to look for it. Then it does something even better. After you find the file for QuickBASIC, the path is stored away automatically in your source code file and used the next time the program is run. There may have to be some slight modification to some programs written in earlier versions of BASIC, so QuickBASIC provides a way to disable the File Not Found Dialog option in the Options menu item of the Run menu.
The compiler is built in so it is very easy to get a stand-alone application up and running. There are several options available when compiling, including 68020 and 68881 support if you can use it. Most of the same compiler options are available here that were available in MS Compiler 1.0. As mentioned before, you may choose to use the default window or use the default menus (File and Edit) if needed. Library resources may be included if the Include MBPCs and MBLCs option is selected. (All the CLR Toolbox libraries have been updated and the resource type changed to MBLC (Microsoft Basic Library Code????) resources. The MBPC type is used to denote pure code resources which can be created with some compilers. A utility program is included to scan a QuickBASIC source file and remove library and toolbox resources which are not used by the application. This will reduce the size of the stand-alone application. ALSO, the toolbox library (formerly called ToolLib) is now installed as MBLC resources in the QuickBASIC application. Therefore, all the toolbox statements are available at all times. You now need to specify a type (&,!, #) for a library call only after DEFSTR; DEFINT no longer requires a type. For example:
DEFINT a-z
DrawText No more exclamations on library invocations!
There have been several new MBLC routines added to QuickBASIC since the last release of MS BASIC. One of these new statements is the Toolbox statement which allows access to other Toolbox ROM routines which are not specifically available as MBLC routines. You will need Inside Macintosh to make full use of this statement. Routines marked NOT IN ROM are not accessible from QuickBASIC with the ToolBox call. You must write an MBPC or MBLC to do this. The syntax for the ToolBox statement is:
ToolBox calltype$, trapnum%, arg1, arg2, ... , argn
The calltype$ argument is a BASIC string variable indicating the type of the ROM call. Procedures are indicated by either P or S, Functions returning boolean results use B, functions returning integers use W and functions returning a long integer (LONGINT) use L. The trapnum% is the trap address of the ROM routine as found in Inside Macintosh. A few samples are given in the manual of some ROM calls. The number of arguments in the ToolBox call will vary depending on the routine that is called.
Sample programs using the ToolBox call are shown below. The first program shows a call to the ROM routine that gets the names of fonts if given an id. The program really isnt of much value except to demonstrate an example use of the ToolBox call. [Make sure to remove all non-printable fonts from the system (i.e. postscript escape fonts) or it will crash; I think it has something to do with zero width fonts.- ed] The second program uses the ToolBox call to get the Macintosh tick count. By using this the benchmark times could have been measured more accurately. The remainder of the program demonstrates the use of the SYSTEM function. The SYSTEM function is used to get system environment information for your program. Getting screen size is one use of the SYSTEM functions available. Other environment information is also available as shown in the program. These functions and the ToolBox calls are explained in more detail in the QuickBASIC manual.
Your old CLR libraries and other libraries you may have created can still be used with QuickBASIC without converting them to the MBLC resource type. Be sure to check to see if the routine already exists in QuickBASIC as a MBLC before using your old routine unnecessarily. You may print lists for comparison purposes with the new version of the Statement Mover program. Statement mover has also been updated to support the MBLC and MBPC resource types.
Youre probably wondering how QuickBASIC does in the benchmark tests. Table 1 shows the benchmark results for QuickBASIC , True Basic and ZBasic. ZBasic and True Basic times have appeared in previous issues of MacTutor and were not retested for this table. I have included them here for comparison purposes. Keep in mind that any one benchmark test does not determine how good a language is. All tests were performed on a Macintosh Plus Computer.
BENCHMARK | MS QuickBASIC* | True Basic | ZBasic
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FOR Loop (Real) | 3 sec | 1.6 sec. | 15 sec.
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Array Lookup (static) | 2 sec. | 20.67 sec. | 1 sec.
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Math Operations
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| Addition | 9 sec. | 22.15 sec. | 52 sec.
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| Subtraction | 10 sec. | 23.23 sec. | 64 sec.
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| Multiply | 12 sec. | 25.55 sec. | 211 sec.
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| Divide | 35 sec. | 35 sec. | 446 sec.
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String Operations
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| Concatenation | 34 sec. | 10.3167 sec. | 10 sec.
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| Pattern Matching | 25 sec. | 12.15 sec. | 6 sec.
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Graphics
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| Line (Basic stmt) | 7 sec. | 61.25 sec. | 6 sec.
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| Horizontal line | 15 sec. | 38.867 sec. | 5 sec.
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| Circle | 20 sec. | 13.4667 sec. | 15 sec.
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| Set Pixel
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| (PSET or PLOT) | 38 sec. | 119.3 sec. | 19 sec.
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File I/O (Floppy Disk)
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| Random READ | 2 sec. | 24.5 sec. | 8 sec.
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| Random WRITE | 24 sec. | 43.48 sec. | 114 sec.
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| Seql. PRINT# | 3 sec. | 17.0667 sec. | 9 sec.
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| Seql. INPUT | 3 sec. | 17.45 sec. | ???
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Sieve of Eratosthenes | 8 sec. | 118.917 sec. | 7 sec.
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Accuracy Benchmark
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| x | 503.54380215 | 503.54380215 | 503.54380215
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| s | 1.23 | 1.224999999999966 | 1.23
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| time | 1 sec. | .88333 sec. | 4 sec.
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* NOTE: QuickBASIC compiled binary version used for all tests except accuracy benchmark.
To obtain optimal performance from compiled QuickBASIC for execution speed it is advisable to use static arrays, turn off array bounds, turn off event checking, generate 68020 and 68881 code if applicable, use SELECT CASE statements instead of IF/THEN/ELSE statements inside loops, and use SHARED (global) arrays when passing to subprograms.
Display Fonts
©Copyright 1988 MacTutor
by Dave Kelly
This program will display all your system fonts
with a sample and by name.
This program uses the ToolBox statement in
QuickBASIC version 1.0
ToolBox I Initialize Toolbox
DEFINT a-z
x=0
FontName$=
FOR i=0 TO 254 Cycle through all the fonts
TEXTFONT(i)
GOSUB GetFontsname
IF FontName$<> THEN
PRINT This is a sample of font #;
CALL TEXTFONT(0):PRINT i; ;FontName$
IF x/10 >1 THEN
x=0:PRINT Click mouse button to continue...
WHILE MOUSE(0)<>1 :WEND:CLS
ELSE
x=x+1
END IF
END IF
NEXT
WHILE MOUSE(0)<>1:WEND
END
GetFontsname: Get the name of the Font with ID = i
TrapNo%=&HA8FF
ToolBox P,TrapNo%,(i),FontName$
RETURN
System Configuration Demo
©1988 MacTutor
By Dave Kelly
This program displays all of the system configuration
data which is returned by the SYSTEM Function.
Also the number of tick counts is read from the
Macintosh directly to get a more accurate time.
ToolBox I: Initialize the toolbox call
start&=0&:finish&=0&
CALL GetTickCount(start&) :Call the tick count routine
Screenwidth=SYSTEM(5) : get screenwidth
Screenheight=SYSTEM(6) : get screen height
WINDOW 1,System Configuration,(4,41)-(Screenwidth-8,Screenheight-8),1
PRINT Macintosh System Version:;SYSTEM(0)
machine=SYSTEM(1) : get machine type
SELECT CASE machine
CASE 0
machineType$=Unknown
CASE 1
machineType$=Mac 512K
CASE 2
machineType$=Mac Plus
CASE 3
machineType$=Mac SE
CASE 4
machineType$=Mac II
END SELECT
PRINT Machine type: ;machineType$
PRINT Running QuickBASIC version ;SYSTEM(2)
Math=SYSTEM(3): Get Math type
SELECT CASE Math
CASE 0
MathType$=Binary Math
CASE 1
MathType$=Decimal Math
END SELECT
PRINT Using ;MathType$
environmentFlag=SYSTEM(4)
IF environmentFlag=0 THEN
PRINT Program is being run from the QuickBASIC environment
ELSE
PRINT Program has been compiled.
END IF
CALL GetTickCount(finish&)
PRINT Total time to run this program was ;(finish&-start&)/60; seconds
END
SUB GetTickCount(Ticks&) STATIC:Get the real number of ticks
TrapNo%=&HA975
Ticks&=0&
ToolBox L, TrapNo%,Ticks&
END SUB
LETTER BAG
Your review of True Basic 2.01 was of special interest to me because Ive been trying to port a library of thirty astronomical programs from CBasic (remember?) and MS Basic to the Mac. As you pointed out, the math libraries and advanced toolkits make True Basic very useful for scientific tasks. However, the many arbitrary differences in syntax from standard Basics has made the translating task very time-consuming and the source level debugging using DO TRACE is crude compared to MacPascal or LSP.
My greatest disappointment has been the poor speed performance. My Mac has the Turbomax accelerator board and 68881 coprocessor both rated at 16 mhz. Since my work involves heavy use of transcendentals, I use the Savage benchmark; here are some results:
MacPascal 2.0 30.1 seconds interpreted
True Basic 2.01 29.1 seconds *
Excel 1.04 12.6 seconds supports 68881
LS Pascal 1.1 4.7 seconds compiled
* This is Its even faster than before. as their ad claims?
Incidentally, they carefully modified the Geneva font so that the capital O and zero [0] are identical; a real gotcha when trying to debug. --Leonard Kalish
Maybe QuickBASIC will be better for you as it can be compiled. Also if you use CLR Libraries MathStatLib you get some of the math routines back. The difference in the Basic syntax is because of the ANSI standard influence of Thomas E. Kurtz, one of True Basics authors. It is interesting that most of the other Basics out there are enough different from the ANSI standard to make translating a difficult task. Thanks for your comments. DK.