PCjs Machines

 Volume in drive A has no label
 Directory of A:\

BUG      BAS       397   2-17-86   3:34p
CALLSHAP BAS       133   4-25-86  10:00a
DEMO     BAS       211   6-10-86   9:47a
EX       BAS       182   4-25-86  10:01a
PPRINT   BAS     22941   6-17-86   8:53a
QB       EXE    186256   6-16-86   2:47p
README   DOC     15580   6-19-86   4:26p
REMLINE  BAS     12913   6-19-86   7:12a
SQUARE   BAS       164   4-25-86  10:02a
TRIANGLE BAS       250   4-25-86  10:03a
UPDATE   DOC      6545   6-03-86   2:05p
USERLIB  ASM     17439   5-27-86   8:09a
       12 file(s)     263011 bytes
                       91136 bytes free

 Volume in drive A is QUICKBAS2JP
 Directory of A:\

QB       EXE    186256   6-16-86   2:47p
BCOM20   LIB    176128   6-13-86  10:55a
        2 file(s)     362384 bytes
                           0 bytes free

This file is divided into two parts. Part 1 contains additions and corrections 
to the QuickBASIC Version 2.0 manual. Part 2 contains information about 
additions and changes to QuickBASIC that were made after the manual was printed.

Part 1: Corrections to the Manual

Page    Correction
----    ----------

71      In the syntax line at the bottom of the page, the "c:buffersize"
        option should be preceded by a forward slash, as follows:

        /c:buffersize

78      Binary files cannot be loaded into QuickBASIC. The note in the middle
        of the page should read:

    QuickBASIC accepts only ASCII files. If you attempt to load a binary
        file, you will get an error. 

152     The stack is preset to 768 bytes, not 512.

222     The EGA card does not support the COLOR statement border parameter. 
        If you have an EGA card installed on your system, using the border 
        parameter will cause unpredictable results.

275     In FIELD statement Example 2, the order of arguments is reversed
        for all string-manipulation functions. The affected section of the 
        program should read as follows:

        .
        .
        .
        IF (ZCHECK$ > "85699" AND ZCHECK$ < "85801") THEN
            INFO$ = PLIST$
            PRINT LEFT$(INFO$,25)
            PRINT MID$(INFO$,16,25)
            PRINT RIGHT$(INFO$,17)
        END IF

283     In the FRE function example, the first line of the example should be
        a $DYNAMIC metacommand, as follows:

        '  $DYNAMIC
        PRINT "Before dimensioning arrays:   " FRE(""),FRE(0),FRE(-1)
        .
        .
        .

286     There is a missing parenthesis in the formula for computing the GET
        graphics statement array size. There should be 3 parentheses after
        the INT keyword, as follows:

        4 + INT(((x2 - x1 +1) * bits-per-pixel + 7)/8) * ((y2 - y1) +1)

297     The two examples comparing the single-line and block forms of the
        IF...THEN...ELSE statement should read as follows:

        Example 1:

        INPUT "Price = ",x
        IF (x >= 10000) THEN DISC! = x * .25! ELSE _
            IF (x < 10000) AND (x >= 5000) THEN DISC! = x * .2! ELSE _
            IF (x < 5000) AND (x >= 1000) THEN DISC! = x * .1! ELSE _
                DISC! = 0
        IF DISC! = 0 THEN PRINT "No discount" ELSE _
            PRINT "Discounted price = "; : PRINT USING "$$####.##";x - DISC!

        Example 2:
        
        INPUT "Price = ",x
        IF (x >= 10000) THEN 
            DISC! = x * .25! 
        ELSEIF (x < 10000) AND (x >= 5000) THEN 
            DISC! = x * .2! 
        ELSEIF (x < 5000) AND (x >= 1000) THEN 
            DISC! = x * .1! 
        ELSE DISC! = 0
        END IF
        IF DISC! = 0 THEN 
            PRINT "No discount" 
        ELSE 
            PRINT "Discounted price = "; 
            PRINT USING "$$####.##";x - DISC!
        END IF

317	The second comment in the example program should read:

        'DOWN key will now be trapped

325     The STEP option example requires a hyphen before the STEP keyword, as
        follows:

        LINE -STEP (10,5)

        The phrase following the example should read:

        "draws a line from (10,10) to the point with x-coordinate
    10+10 and y-coordinate 10+5, or (20,15)."

396     The variable in the first line of PLAY statement Example 1 should be
        SCALE$, not SCALES$:

        SCALE$ = "CDEFGAB"

410     In the example, all references to the file STORINVENT should be changed 
        to INVENT.DAT. The file argument to both OPEN statements should be
        the same file, INVENT.DAT.

418     The first entry in the "Arguments" column should be (x,y), not
        (x1,y1).

420     Images cannot be scaled with the PUT graphics statement. Only one set
        of x,y coordinates can be specified as arguments to PUT. All text
        after "Because you can specify..." in the second paragraph, and all of 
        the following paragraph, should be ignored.
        
448     In the description of the SCREEN statement arguments, the first line
        under the SCREEN 2 heading should refer to high-resolution graphics 
        instead of medium-resolution graphics, as follows:

        * 640 x 200 pixel high-resolution graphics

474     The example for the STR$ function should read as follows:

        DEF FNNUM$(X)
            X$ = STR$(X)
            LENGTH = LEN(X$)
            IF LEFT$(X$,1) <> "-" THEN LENGTH = LENGTH - 1
            FNNUM$ = RIGHT$(X$,LENGTH)
        END DEF

        PRINT "Enter 0 to end." : NUM = -1    'Corrected line
        WHILE NUM
            INPUT "Find cosine of: ",NUM
            IF NUM THEN PRINT "COS(" FNNUM$(NUM) ") = " COS(NUM)
        WEND

482	In the example, the input to the prompt "Pattern to be searched 
        for?" must be SUB (not "sub") in order to get the output shown.

525     Add DEBUG to the list of reserved words.

536     If you are using a version of DOS earlier than 3.0, use the PATH command
        instead of the SET command to define the PATH variable. Using SET under 
        earlier versions of DOS can cause the PATH variable to work incorrectly 
        for some path specifications that contain lowercase letters.

546 &   The stack is preset to 768 bytes, not 512.
547

570     The explanation for the error message "Too many files" should read:

    This error most commonly occurs when a file open is attempted that 
        exceeds the limit set by the FILES= parameter in the CONFIG.SYS
        file. It also occurs when the per-directory file limit is exceeded by 
        an attempt to create a new file with the SAVE or OPEN statement.
        Refer to your DOS manual for the number of files permitted in a 
        directory.

Part II: Additional Information

1. Executing command buttons

Note that pressing RETURN always executes the command button with the 
double outline, regardless of which button is highlighted. Even if you
have moved the highlight to another button, pressing RETURN will execute the
default command. To execute the command in the highlighted button, press 
SPACEBAR.

2. The QB.INI initialization file

QB.INI is an initialization file QuickBASIC uses to set the View
menu Options settings and the the File menu Autosave command.
Upon exiting from QuickBASIC, if you have modified any of the Options 
settings or the state of the File menu Autosave command, these 
changes are written to QB.INI. Note that QB.INI is not supplied on any 
of the product disks. It is created only when a modification to the Options 
or Autosave settings occurs. If you only use the default settings, QB.INI 
is never created. 

When QB.INI is created, it is placed in the current directory. When 
QuickBASIC starts, it looks for QB.INI in the current directory, then in 
the locations specified by the PATH environment variable.

3. Source-file line termination

QuickBASIC 2.0 requires a CR/LF (carriage return/line feed) sequence at 
the end of each line. If only carriage returns are present, QuickBASIC 
reads the first 255 characters only, and continues without producing an error
message. If only linefeeds are present, the file will appear to read in
correctly, but the last character of each line will be missing. If
you use an editor that places only a CR or an LF at the end of a line
you will need to modify your source files so they have the correct
sequence at the end of each line. The following program examines the
end of each line in a file and inserts a carriage return, linefeed, or
both if needed.

    DEFINT A-Z
    cr = 13 : lf = 10
More:
    CLS
    INPUT "File (.BAS) ", inpfile$
    ON ERROR GOTO NoFile
    OPEN inpfile$ + ".BAS" FOR INPUT AS #1
    ON ERROR GOTO 0
    OPEN inpfile$ + ".NEW" FOR OUTPUT AS #2
    OPEN inpfile$ + ".BAK" FOR OUTPUT AS #3
    prevcr = 0
    WHILE NOT EOF(1)
    filechar$ = INPUT$(1, #1)
    PRINT #3, filechar$;
    IF ASC(filechar$) = cr THEN
        prevcr = 1
        PRINT #2, filechar$;
    ELSEIF ASC(filechar$) = lf AND prevcr THEN
        prevcr = 0
        PRINT #2, filechar$;
    ELSEIF ASC(filechar$) = lf AND NOT prevcr THEN
        PRINT #2, CHR$(cr);
        PRINT #2, filechar$;
    ELSEIF prevcr THEN
        prevcr = 0
        PRINT #2, CHR$(lf);
        PRINT #2, filechar$;
    ELSE
        PRINT #2, filechar$;
    END IF
    WEND
    CLOSE
    KILL inpfile$ + ".BAS"
    NAME inpfile$ + ".NEW" AS inpfile$ + ".BAS"
    INPUT "Anymore (Y/N) ", more$
    IF more$ = "y" OR more$ = "Y" THEN GOTO More
    SYSTEM
NoFile:
    number = ERR
    IF number = 53 THEN
    CLS
    INPUT "No such file ", z$
    RESUME More
    ELSE
    ON ERROR GOTO 0
    ERROR number
    END IF

4. Using CALL ABSOLUTE with in-memory compilation

CALL ABSOLUTE is considered an external subroutine by the QuickBASIC
compiler. This subroutine is in the user library USERLIB.EXE, supplied 
on QuickBASIC disk #1. 

5. Compilation errors

When an error is detected during compilation, code generation stops. This
allows for faster compilation, but has the side effect that some errors may
be reported that are not errors. When the original error is corrected, 
these side effect errors will go away. For example, the statements

FOR I = 1
    .
    .
    .
NEXT I

will generate two errors, "Missing TO" and "NEXT without FOR". When
the FOR statement is changed to read "FOR I = 1 to 10" both errors
are corrected.

6. COMMAND.COM, the SHELL statement and the Shell command

QuickBASIC requires COMMAND.COM before it can execute a SHELL statement or
the File menu Shell command. QuickBASIC looks first in the directory 
specified in the COMSPEC environment variable, then in the current directory.

7. Using SHELL in a subroutine

The SHELL statement does not compress memory. If not enough contiguous
memory is available, (for example, if many CHAIN statements have been
executed, or several dynamic arrays were allocated then erased), a SHELL
statement may fail with an "Out of memory" memory error.

8. Using the SHELL statement with DOS 2.X

If you are using a 2.X version of MS-DOS, programs that contain SHELL 
statements may not exit correctly. This is due to a known problem in DOS 
2.X. The problem occurs when DOS reloads the transient portion of the 
command processor into high memory. 

To exit QuickBASIC after executing an in-memory program that contains 
SHELL statements, when the program finishes running choose Shell from the 
File menu, then type "exit" at the MS-DOS prompt.

When stand-alone executable programs exit, the message "Invalid COMMAND.COM" 
may appear. If so, you must restart your system. If you compile using 
BRUN20.COM the program will, in most cases, exit properly.

Another solution is to upgrade your DOS version to 3.X.

9. Running terminate and stay resident programs from the File menu Shell

Do not run terminate and stay resident programs while executing the Shell
command from the File menu. When a Shell command is executed, QuickBASIC
is compressed into the smallest memory possible. The terminate and stay 
resident program will occupy memory required by QuickBASIC, and it will
not be possible to compile or run a program, or do anything that
allocates memory.

10. Changing directories from the File menu Shell command

    If you change directories after executing the Shell command from the File
    menu, this directory is the current directory when you return to QuickBASIC.
The Load command will start from this directory, and when you quit QuickBASIC
    you will be in this directory.

11. Using BRUN20.EXE with user libraries

    The runtime module BRUN20.EXE obtains the user library using the name the
    program module was compiled with. All independently-compiled program modules
    that will be linked together must have been compiled with the same user 
    library using the same name, or an error occurs at runtime.

12. Using /l with nonreferenced libraries

    User libraries specified with the /l option are pulled into the
    executable file regardless of whether the program requires them.

13. The user library search path

    If path information is provided with the qb command's /l option, as in
    
    qb progname /l \src\lib\mylib.exe

    no path search is performed. If the library is not in the specified location
    an error occurs. If no path information is provided, the current directory
    is searched, then the directory specified in the LIB environment variable.

14. Using the IBM Advanced 101-key keyboard

    You cannot use the alternate arrow and cursor movement keys to select text.
    You can use them to move the cursor. To select text, use the cursor
    movement keys on the numeric keypad. (Note that the NumLock key must be
    off to use the numeric keypad's cursor movement keys.)

15. Using the Tandy 1000 Personal Computer Keyboard

    The cursor keys on the Tandy 1000 keyboard cannot be used with
    QuickBASIC. You must use the numeric keypad to move the cursor 
    and select text. The keys are mapped as follows:

    Cursor Movement     Number
    ---------------     ------
        END               1
        DOWN              2
        PGDN              3
        LEFT              4
        RIGHT             6
        HOME              7
        UP                8
        PGUP              9

16. Graphics mode statements

    A graphics adapter card is required if you are using the following 
    statements:

    CIRCLE
    COLOR (screen modes 1-10)
    DRAW
    GET (graphics)
    LINE
    PAINT
    PALETTE
    PCOPY
    PMAP
    POINT
    PRESET
    PSET
    PUT (graphics)
    VIEW
    WINDOW

17. EGA card restrictions

    The EGA card does not support the COLOR statement border parameter. Using
    the border parameter causes unpredictable results.

    QuickBASIC does not support 43-line mode.

18. Program capacity

    Because the Debug option generates extra code, extremely large programs 
    that are compiled with the Debug option may exceed the memory limits of 
    your computer.
        
19. Object file size

    Programs compiled with the Debug option (the default) create larger
    object files than programs compiled without the Debug option.

20. Using the PEN function when a mouse driver is present

    The mouse driver intercepts PEN function BIOS calls and redirects them to 
    the mouse. If you don't want to use the mouse as a lightpen, call mouse 
    function 14 to disable the mouse's lightpen emulation flag, which is 
    on by default. Mouse function 13 turns lightpen emulation back on. For 
    example, the following code turns mouse lightpen emulation off:

    CALL MOUSE(14,0,0,0)

    See your mouse manual for more information.

21. Editing INPUT statement responses

    The input editor supplied with QuickBASIC is a line editor only. This 
    means you can move and edit only horizontally. Attempts to use the 
    UP, DOWN, PGUP and PGDN cursor keys produce a beep.