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Volume 1, Number 1 November 1, 1989 ************************************************** * * * QBNews * * * * International QuickBASIC Electronic * * Newsleter * * * * Dedicated to promoting QuickBASIC around * * the world * * * ************************************************** The QBNews is an electronic newsletter published by QBNews. It can be freely distributed providing NO CHARGE is charged for distribution. All articles in QBNews are copyright by QBNews. All program code appearing in QBNews is released into the public domain. You may do what you wish with the code except copyright it. QBNews must be distributed whole and unmodified. Copyright (c) 1989 by QBNews. The QBNews Page i Volume 1, Number 1 November 1, 1989 ---------------------------------------------------------------------- T A B L E O F C O N T E N T S 1. From the Editors Desk The Mission of the QBNews by David Cleary .................... 1 2. Feature Presentation What I Would Like To See by David Cleary ..................... 3 3. Who ya gonna call? CALL INTERRUPT QuickBASIC Directories by Hector Plasmic ..................... 4 4. Under The Hood Memory Moves with QB by David Cleary ......................... 6 5. The Tool Shed MicroHelp's QB Optimizer by Larry Stone ...................... 7 6. Product Announcements P.D.Q. ....................................................... 9 7. The BUG Report QB Quirks .................................................... 11 8. CTL-Z Closing Comments by David Cleary ............................. 13 9. Address Address ...................................................... 14 The QBNews Page ii Volume 1, Number 1 November 1, 1989 ---------------------------------------------------------------------- F r o m t h e E d i t o r s D e s k ---------------------------------------------------------------------- The Mission of the QBNews by David Cleary Welcome to the first issue of the QBNEWS. With the growing popularity of QuickBASIC, a newsletter was needed to help users get the most out of the language. The QBNEWS has 3 goals. The first is to inform people about what is out there as far as tools are concerned. The second is to teach users how to get the most out of the QuickBASIC product. And last but not least is to share code. To accomplish the first goal, the QBNews will contain a review of a commercial or shareware product in every issue. Many times I have come across a problem and I wasn't aware that the solution was available. We hope to provide a fair review o f what is out there to let you make an informed decision on whether the product will fit your needs. The reviewers are actual users of the product just like you and me. They will let you know if the product does what it says and report any problems t o you. The QBNews will also contain new product announcements from anybody who has a QuickBASIC related product to announce. This will keep you informed as to what is happening on the QuickBASIC scene. We will have a variety of features to help you get the most out of QuickBASIC. Hector Plasmic will have a regular column on CALL INTERRUPT. CALL INTERRUPT is one of the most powerful yet least understood features in QuickBASIC. With Hector's help, you will learn how to use it and you will get code that you can plug directly into your programs to access DOS and BIOS system calls. Another feature that will appear from time to time is UNDER THE HOOD. This will feature ways to access interna l QuickBASIC routines to get power you thought you had to go to third party assembly libraries to get. Now comes the good part. The CODE. We want to include as much code as possible. You can either choose to use this code as is, or even better, learn what it is doing and come up with improvements. I would like to see the development of real ap plications from start to finish that span issues. I also want to see lots of contributions from all you out there with useful subroutines that you feel everyone would benefit from. All code published in the QBNEWS is put into the public domain. That means you can do whatever you want with it except copyright it. If we all work together to learn and share, we can make QB the language of the 90's. Every QB user will benefit by expanding the popularity of QuickBASIC and the best way to do that will be to knock down the "YOU CAN'T DO THAT WITH BASIC" walls. In order for this newsletter to succeed, we need your help. Believe it or not, writing is one of my least favorite activities. This newsletter is going to die without contributions from YOU. This is both code AND feature articles. Also we nee d suggestions on what you want to see in future issues. QBNEWS is going to start out being published once every two months. If I see some support, we can make it a monthly. The QBNews Page 1 Volume 1, Number 1 November 1, 1989 You don't have to be an expert at QuickBASIC to contribute either. The only t hing I ask is NO LINE NUMBERS PLEASE <grin>. As Bartles and James say, "Thank you for you support." The QBNews Page 2 Volume 1, Number 1 November 1, 1989 ---------------------------------------------------------------------- F e a t u r e P r e s e n t a t i o n ---------------------------------------------------------------------- What I Would Like To See by David Cleary This is our FEATURE section. It is a little bare in this issue though. What I want to see in this section is a group of articles all pertaining to a chosen topic. To achieve this, I need people who want to write these articles. Since I started this newsletter, I am choosing the next Feature Presentation. I want articles on how to use the various tools that Microsoft supplies with their languages. These should be tutorials on how to use them and any tips you might have stumbled across while using them. I still don't know how to use every feature of the QB debugger and I know there are quite a few out there who don't know how to compile and link from the command line. Not all of these tools are provided with QuickBASIC but they do come in handy sometimes. The tools I want to cover are BC.EXE LIB.EXE LINK.EXE QB Debugger Codeview HelpMake NMake Exemod and the like This list could be expanded if I have left out anything. If you are interested, read the final notes on how to reach me. Thank you. The QBNews Page 3 Volume 1, Number 1 November 1, 1989 ---------------------------------------------------------------------- W h o y a g o n n a c a l l ? C A L L I N T E R R U P T ---------------------------------------------------------------------- QuickBASIC Directories by Hector Plasmic While QuickBASIC has a lot of features, there are a few it lacks. Ever wanted to do a directory search? Chances are you had to Shell to DOS, create a temporary file by redirecting the DIR command, then return to QB and read the file line-by-line, parsing out the filenames. Either that or you resorted to a third-party library function. It's not necessary. QB can be cajoled into doing directory searches by utilizing the DOS directly via Interrupt. Interrupt 21h functions 4Eh and 4Fh do find-first-match and find-next-match respectively. If the call to these functions is successful, information on the matched file is placed by DOS into the current DTA (disk transfer area) as follows: Bytes 0-20 = (reserved, used during findnext calls by DOS) Byte 21 = attribute of matched file Bytes 22-23 = file time Bytes 24-25 = file date Bytes 26-27 = least significant word of file size Bytes 28-29 = most significant word of file size Bytes 30-42 = filename and extension in form of ASCIIZ string All this brings up another question: where is the current DTA? The answer is given by a call to interrupt 21h function 2Fh, which returns the DTA's offset in BX and the segment in ES. So, we make a call to interrupt 21h with register .ah set to 2Fh like this: InRegs.AX = &H2F * 256 'Remember, .ah is the high-byte of .ax INTERRUPTX &H21, InRegs, OutRegs And retrieve the returned information: DTASeg = OutRegs.ES 'Segment of current DTA DTAOff = OutRegs.BX 'Offs of current DTA If we now say DEF SEG = DTASeg we can directly PEEK into the DTA, wherever it may be. Okay, we know where the data will be, now how do we get it there? Like this: FLName$ = "*.*" + CHR$(0) 'ASCIIZ filespec (null terminated) InRegs.AX = &H4E * 256 'Which function (4Eh) InRegs.CX = 0 'Attribute (normal) InRegs.DS = VARSEG(FLName$) 'Segment of ASCIIZ filename InRegs.DX = SADD(FLName$) 'Offset of ASCIIZ filename InterruptX &H21, InRegs, OutRegs The QBNews Page 4 Volume 1, Number 1 November 1, 1989 This calls interrupt 21h function 4Eh and places the information on the first matched file into the DTA. There's a catch, though. There may not be a matching file. If there isn't, this function returns an error by setting the carry flag and returning a code in AX. We can check for this with: IF OutRegs.Flags AND 1 THEN WhichError = OutRegs.AX The two possible errors are "invalid path" (2h) and "no (more) matching file(s)" (12h). Now all that remains is to PEEK the information out of the DTA and do something useful with it. FINDEM.BAS is a sample program together with a Function FindFirst that will do directory searches for you. Modify the main module code to load the filenames into an array or whatever you need it to do. The QBNews Page 5 Volume 1, Number 1 November 1, 1989 ---------------------------------------------------------------------- U n d e r T h e H o o d ---------------------------------------------------------------------- Memory Moves with QB by David Cleary This is a section that will appear from time to time if the information presents itself. Although not support certain functions directly, QuickBASIC does have internal routines that can be very helpfull. When using internal QuickBASIC routine s, you must use the DECLARE statement and give the routine an ALIAS. This is because the routines internal to QB have names that are not allowed in QuickBASIC. This is mostly because they contain either the $ or _ characters within them. The only pro blem when using internal QB routines is that I haven't found a way to use them in the environment. The routine we are going to learn about today is called B$ASSN. QuickBASIC uses this routine for a number of things. Among them is copy userdefined types to each other and copy fixed length strings to variable length strings. What we will use it for is to copy a block of memory to another location. The syntax for B$ASSN is: B$ASSN(FromSeg, FromOfs, NumBytes, ToSeg, ToOfs, NumBytes1) In order to use it in a QB program, we need to use the following DECLARE statement: DECLARE SUB MemMove ALIAS "B$ASSN" (BYVAL FSeg%, BYVAL FOfs%,_ BYVAL Bytes1%, BYVAL TSeg%, BYVAL TOfs%, BYVAL Bytes2%) You can change the name MemMove to whatever you like. The program SCRNSUBS.BAS show how to use this routine to save and restore screens. This routine is very efficient in doing this paticular job but because of other things it has to do, it w ill bring all the string handling routines into your program. So, if you are planning on using this routine in a program that already uses the string handling routines, there will be no effect on file size. If you don't use the same number of bytes, QB will truncate it. Be carefull not to destroy memory by writing where you don't belong. The QBNews Page 6 Volume 1, Number 1 November 1, 1989 ---------------------------------------------------------------------- T h e T o o l S h e d ---------------------------------------------------------------------- MicroHelp's QB Optimizer - How to Save Some Bytes by Larry Stone It seems that MicroHelp, Inc. releases a new library for QB at the rate of one every other week. Their latest release is "QB/Pro Volume 7" or, for short, "QB Optimizer". The QB Optimizer is comprised of four exe files: PP.EXE - the pre- processor, OPT.EXE - the optimizer, XREF.EXE - the cross-reference utility, CHECKX.EXE - to inform you which XModules can be linked with your programs. The package also includes seven XModules used to link with your programs to reduce exe size, three object modules to set various screen displays, one object module used as a replacement for QB's INKEY$ function, one object module used to replace QB's LOCATE command, one link library to use in lieu of the supplied object modules, one QLB library for use with QB's environment, and some sample programs to get you started. Question: Does MicroHelp give you all you need to effectively use the QB Optimizer? Answer: No! If, for example, you desire to use the XFLOAT module to reduce your program by 9386 bytes and you have used QB's VAL or STR$ functions, then you must buy MicroHelp's "QB/Pro Volume 2". If your program uses QB's PRINT USING then you need to buy MicroHelp's "Mach 2" package. Because MicroHelp has produced some outstanding packages for compiled BASIC programs, I already had these packages and, therefore, incurred no additional expense. However, I was dissapointed when I discovered in the manual that I could not use the XFLOAT module if my programs use QB's SETMEM command. If you are developing a TSR program in QB 4.x and link it with MicroHelp's Stay-Res module (an excellent buy), you *MUST* use SETMEM to re-allocate your dynamic arrays to the bottom of the heap. I write TSR programs using Stay- Res and would love to reduce their size by another 9386 bytes. But no can do because the XFLOAT object cannot work with SETMEM. MicroHelp's "Volume 2" has one outstanding ditty called, "MhCopy" which opens up all available DOS or EMS memory, reads your file into this free memory, then copies it to your designated location. It is a faster procedure than the DOS COPY command and returns error codes that can be acted upon without error trapping. It requires SETMEM. Need I say more? When I called MicroHelp and complained, they informed me that no one else seems to be upset about this and therefore, they don't intend to add a replacement for SETMEM. If you use MicroHelp products, give them a call and ask for a replacement for SETMEM. Do the XModules work? Well, I tried it with their supplied example called, FULLCUR.BAS and it bombed. XFLOAT gave me a duplicate The QBNews Page 7 Volume 1, Number 1 November 1, 1989 definition error with a procedure already in existence in my BCOM40.LIB. XINPUT.OBJ does not work without XINTS.OBJ and XINTS.OBJ caused my program to lock up my system. When I linked without the offending modules, my exe size was cut in half. I contacted MicroHelp about this problem, and, as always, their support was above and beyond what most other companies would offer. As instructred, I returned my diskette and one week later my diskette was returned with their latest routines and a nice letter. The letter informed me that QB Optimizer would not work with the QB 4.00 libraries and that I needed to have Microsoft send me version 4.00b. I immediately ordered my free update from Microsoft. If all the modules worked for me, the final exe size of the FULLCUR program should have been 3343 bytes using BC 4.00b (3311 using BC 4.50). What I did like about this package was PP.EXE - very nice. CHECKX.EXE is also a slick program - it worked as expected. OPT.EXE was, in my opinion, useless - I already write readable, structured code. The XREF.EXE utility seems a little cumbersome to use - I think its most useful feature is as a utility to "weed out" variables that are assigned and never used. Who should use this package? As MicroHelp states in their manual, "The XModules are not for use by the 'faint of heart'. This means that if you are not proficient with programming in QB, you should not consider buying this package. Do I like the QB Optimizer? Even without the ability to work with SETMEM, there are many applications that I could write that would benefit with the Optimizer. If you are presently using MicroHelp asm libraries for your QB programs, the Optimizer is a must. The QBNews Page 8 Volume 1, Number 1 November 1, 1989 ---------------------------------------------------------------------- P r o d u c t A n n o u n c e m e n t s ---------------------------------------------------------------------- P.D.Q QuickBASIC Replacement Library $99.00 Cresent Software 11 Grandview Ave. Stamford, CT 06905 203-846-2500 P.D.Q. is a replacement linking library for use with Microsoft QuickBASIC version 4.0 or later. When a compiled BASIC program is linked with PDQ.LIB instead of the usual BCOM library supplied with QuickBASIC, the .EXE file size will be reduced dramat ically. Code size reductions of six to one are typical for small source files, however the actual improvement will of course depend on the individual program. Program execution speed when using P.D.Q. will likewise be greatly improved. Applications t hat have been linked with P.D.Q. will be noticeably smaller than an equivalent written in C, and will in fact be closer to pure assembly language. P.D.Q. also features a number of important language extensions, including TSR program support and interrupt handling. Writing TSR programs and interrupt handlers usually requires an extensive knowledge of assembly language, however P.D.Q. includes a full compliment of routines that allow you to do this using only QuickBASIC commands and simple extensions. Many other important features are provided with P.D.Q., and we will get to those shortly. The primary purpose of P.D.Q. is to create .EXE programs that are as small and fast as possible. There is virtually no error checking beyond simple syntax errors which are caught at compile time. However, because P.D.Q. is based on Microsoft QuickBAS IC, programs may also be developed and tested in the more secure enviroment BASIC offers, and then linked for maximum efficiency using the P.D.Q. library once they are working correctly. P.D.Q. has been designed as a subset of the recognized industry standard BASIC that has been established by Microsoft. Programs that are created using P.D.Q. are inherently "well-behaved", and may thus be run under operating systems such as Microsoft Windows and DesqView without any additional effort. Some programmers, paticularly those who don't ordinarily program in BASIC, may wonder why we would select BASIC as the core language for P.D.Q. Simply put, BASIC is the easiest of all the high-level languages to use, and nearly every programmer is al ready familiar with it. Microsoft QuickBASIC provides all of the features necessary for modern, structured programming. Further, the BC.EXE compiler supplied with QuickBASIC is as powerful and capable as any available language compiler. P.D.Q. progra ms may be written and debugged in the convenient enviroment QuickBASIC offers, and then linked for maxium performance when creating the final program. The QBNews Page 9 Volume 1, Number 1 November 1, 1989 Our goal in designing P.D.Q. was to place code size and execution speed above all other considerations. Many of QuickBASIC's most advanced features are not included, and some commands have been implemented in a slightly different manner. Therefore, w e'll begin by looking at what has been omitted. Please understand that in all cases where a QuickBASIC feature is not supported, the improvement in speed or code size was the deciding factor. The primary purpose of P.D.Q. is to create extremely small programs that execute very quickly. If you intend to write a mojor accounting program or relational database, you will probably be better off using regular QuickBASIC. P.D.Q. provides no support for floating point numbers -- only integers and long integers may be used. However, fixed point numbers may be accommodated by treating them as long integers, and then formatting them when needed. A special routine (Dollar$ ) is provided precisely for this purpose. There is no built-in support for graphics. Though you can easily switch the PC's screen to any of the graphics modes supported by the hardware, we have not provided library routines for drawing lines, boxes, or circles. These may be added in a future version of P.D.Q., but if those features are needed now, other third- party packages are available. We are about to add a full set of communications routines. These will provide enhanced features over what is built into QuickBASIC. The QBNews Page 10 Volume 1, Number 1 November 1, 1989 ---------------------------------------------------------------------- T h e B U G R e p o r t ---------------------------------------------------------------------- QB Quirks Reprinted from QUIRKS.ARC from MicroHelp, Inc. This section contains exerts from Quirks.arc. This file probably is the most comprehensive bug report on QB. We will include all new bugs in this newsletter as they come up. We will also include interesting quirks. This file is maintained by Mark Novisoff of MicroHelp, Inc. Much of the information was contributed by members of MicroHelp's BASIC Users Group, users of the MSSYS forum on Compuserve and users of Mach 2, Stay-Res, The MicroHelp Toolbox and the QB/Pro Professional series. If you have additional information that should be added, please send it to: Mark Novisoff MicroHelp, Inc. 4636 Huntridge Drive Roswell GA 30075 Compuserve ID 73047,3706 in MSSYS (Microsoft Systems Forum) If possible, please include a *small* sample program that will demonstrate the problem and cause it to happen whenever the program is run. _____________________________________________________________ Using CALL with literals takes lots of stack space. (89/10/10) ' Demonstrate the effect on stack space when using literals ' in CALL statements. ' First, run the program as is and note the low point for ' stack space. Then REM the line with variables in the CALL ' and unREM the line with literals and run the program again. ' Note that the low stack point is ten bytes lower when ' literals are used. In a large program with a lot of CALL ' statements, this can really add up. DEFINT A-Z PRINT "Lowest amount of stack space before CALL:"; FRE(-2) A% = 1 B% = 2 C% = 3 D% = 4 E% = 5 ' REM next line for second pass CALL TestStack(A%, B%, C%, D%, E%) ' UNREM next line for second pass 'CALL TestStack(1, 2, 3, 4, 5) PRINT "Lowest amount of stack space after CALL:"; FRE(-2) The QBNews Page 11 Volume 1, Number 1 November 1, 1989 SUB TestStack (A%, B%, C%, D%, E%) END SUB _____________________________________________________________ Sample program #35. Demonstrates a problem using SWAP and CONST in QB 4.50 (89/09/07) ** Warning - this program will crash your system ** Load the following program into QB4.50 and press F5: const Nul$="" z$="hello" swap z$,Nul$ QB4.50 gives different results, depending on if Nul$ is "" or has a length. QB4.00b correctly traps the error of trying to SWAP a constant. The QBNews Page 12 Volume 1, Number 1 November 1, 1989 ---------------------------------------------------------------------- C T L - Z ---------------------------------------------------------------------- Closing Coments by David Cleary Well, the first issue of the QBNews is done. To tell you the truth, I am a little disappointed. I don't feel that this issue has fufilled its mission but it is a start. I am hoping by getting this off the ground, an overwhelming amout of support will start to flow. We need code. We need articles. We need your help! Special thanks to Larry Stone and Hector Plasmic who have given their time to write articles. I know that Microsoft has sold over 500,000 copies of quickBASIC so if only .005 % of these users contributed something to this newsletter, we would be a big success. In the next issue, look for Reader Mail along with the Swap Shop. The Swap Shop will comprise of small useful subroutines that you readers have sent in. We need more code for this newsletter and its got to come from you. The QBNews Page 13 Volume 1, Number 1 November 1, 1989 ---------------------------------------------------------------------- A d d r e s s ---------------------------------------------------------------------- If you wish to submit something for publication in the QBNews, you can reach me in a number of ways. By U.S. Mail David Cleary Lakeview Terrace Ext. Sandy Hook, CT 06842 The QBNews will have a PO Box by the next issue. I can also be reached on FIDONET at 1:141/730, Compuserve as 76510,1725, Prodigy as HSRW18A, and on the QUIK_BAS Echo. If you want to announce a new shareware or commercial product in the QBNews, submit it as an ASCII file. Keep it under 70 lines and make it an announcement and not a review. If you would like to review a commercial or shareware product, contact me first so we don't have more than one person writing the same review. The QBNews Page 14