


      readme.dos (c)Copyright Sequiter Software Inc., 1990-1994.
         All rights reserved.
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                             Table of Contents

         I.    Errata and Changes
                  
         II.   CodeBasic Error Dislay using u4MsgBox

         III.  Using CodeBasic with PDS 7.1

         IV.   Preparing applications for Codeview Debugging

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         This electronic documentation file has been suitably 
         formatted for hard-copy printing.  To print this document, 
         simply direct the file to your printer, using the 'print' 
         command. 
                   eg. print readme.dos 


         ----------------------------------------------------------

   I.    Errata and Changes 


      1. The User's Guide refers to two examples projects, BEGIN.MAK and
         USER.MAK. Both projects contain a .BAS and a .FRM module of the 
         same name. ( BEGIN.BAS/FRM & USER.BAS/FRM )
 
         Under DOS some of these files have been renamed slightly for
         compatiblity reasons:

              DOCUMENTED NAME:              FILE NAME FOR DOS EXAMPLES

              BEGIN.BAS                     BEGIN.BAS
              BEGIN.FRM                     BEGIN_.FRM

              USER.BAS                      USERS.BAS
              USER.FRM                      USERS_.FRM
              USER.MAK                      USERS.MAK
         
         The appending of the underscore character to the .FRM module names
         is to ensure unique .OBJ file names when the modules are compiled.
         The USER.* file names have been changed to USERS.* because the 
         VB DOS compiler will not compile any file with a root name of
         'USER'.


      2. Because the CodeBasic libraries are quite large,it may be difficult 
         to run the USERS.MAK project from within the VB DOS environment. A 
         batch file has been provided to compile the application into a 
         stand-alone .EXE that can be run from the command line. The batch 
         file is called USERAPP.BAT.


      3. Throughout the examples documented, any function that returns
         a pointer is usually tested in the following manner:

              db = d4open( cb, "TEST" )
              if db > 0 Then
                 MsgBox "It Worked"
                 .
                 .
                 .

         Under DOS, valid pointers can also be negative numbers. Thus all
         example code has been modified to test returned pointers for any
         non-zero value as shown below:

              db = d4open( cb, "TEST" )
              if db <> 0 Then
                 MsgBox "It Worked"
                 .
                 .
                 .


      4. If you are using the Standard Edition of VB DOS, modify the
         support files V4LI.BAT and V4LL.BAT, and change each occurence of
         'vbdrt10e' to 'vbdrt10'. For example, in V4LI.BAT:

              Change from:

         link /nod:vbdrt10e %1 %2 %3 %4 %5 %6 /Se:200,,,v4foxdeb vbdos,;


              To:

         link /nod:vbdrt10 %1 %2 %3 %4 %5 %6 /Se:200,,,v4foxdeb vbdos,;


         In addition the example batch compile files, such as BROWSAPP.BAT, 
         all refer to 'vbdrt10e'. If you are using the Standard Edition of
         VB DOS, change any occurrences in these files to 'vbdrt10'.


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   II.   CodeBasic Error Dislay using u4MsgBox

         
         The source code module V4MISC.BAS is compiled into each
         version of the CodeBasic library. This file contains
         BASIC functions used by CodeBasic to perform a few utility
         tasks, such as displaying error messages.

         This file, which is located in the directory \DSUPPORT, can
         be modified and recompiled into your CodeBasic library. To
         recompile the module use the following commands:
         
              bc /d/o/t v4misc.bas

         To replace a new compiled version into your CodeBasic library, 
         use the LIB command as follows:

              LIB <library name> -+v4misc;

         There is a separate version of V4MISC.BAS for PDS 7.1 applications
         located in the directory \DSUPPORT\PDS. Refer to section III.

         The main reason for modifying this file would be to alter or
         disable the display of CodeBasic error messages. The error
         messages are displayed using the VB 'MsgBox' function.
         The name of the CodeBasic function that uses 'MsgBox' is called
         u4MsgBox().

         You can modify u4MsgBox() in any way you wish. You can even disable 
         all error messages by changing the function to do nothing.


         ----------------------------------------------------------

   III    Using CodeBasic with PDS 7.1

         Because of its close association with VB DOS, PDS 7.1 can
         also be used with the CodeBasic libraries with some changes
         and observations.

         1.   As mentioned in section II, CodeBasic normally uses the 
              VB DOS 'MsgBox' function to display error messages. 
              
              Because PDS does not support the 'MsgBox' function, you will
              have to remove the VB DOS version of V4MISC.OBJ from the 
              CodeBasic library and replace it with the compiled version 
              found in \CB51\DSUPPORT\PDS. The u4MsgBox() function in this 
              version simply uses 'print' statements to output error 
              messages.
              
              Use the LIB command as outlined in section II to do the 
              replacement. If you wish, you may also make modifications to 
              u4Msgbox() to accomodate your own error handling process. If
              you do, simply recompile the file using the PDS compiler and 
              then LIB it into one of the CodeBasic libraries as described 
              in section II. 

              
         2.   When linking an application, you will recieve two 
              'unresolved external' errors and a 'symbol defined more
              than once' error. They unresolved symbols are:

                        '__environ' and  'STKHQQ'
              
              and the duplicate symbol is 

                        'U4MSGBOX'.
              
              These can safely be ignored.


         3.   The CodeBasic User's Guide deals with memory limitations in 
              the VB DOS environment. For the most part, this section can be
              ignored, as it is not pertinent under PDS, except for the
              sections on SETMEM() and STACK. Please read these sections 
              carefully.

         4.   The syntax for calling d4init() from PDS is

                   cb = d4init
              
              Note that there are no trailing parenthesis after the 
              function name as you would normally find in VB syntax.

              
         5.   The subdirectory \CB51\DSAMPLES\PDS contains the source code
              for the PDS versions of the BEGIN and USERS examples documented
              in the CodeBasic User's Guide (BEGIN*.* and USER*.*). 
              The source for these examples have been modified to accomodate 
              PDS and are slightly different than listed in the CodeBasic 
              manual.

              In order to compile these examples with the PDS compiler,
              copy BEGIN*.* and USER*.* into the \CB51\DSAMPLES directory,
              overwriting the VB DOS versions of these files.

              Use the corresponding batch files BEGINAPP.BAT and
              USERAPP.BAT to compile, link and run the applications.
              

         6.   Because the CodeBasic libraries are now built with 
              Microsoft C 7.0, it is no longer possible to build a PDS
              quick library without using a more current linker than the
              version supplied with PDS 7.1 ( ver 5.1 ). The linkers 
              supplied with Microsoft C 6.0/7.0 or VB DOS will all
              work.
              
              Even if you successfully build a PDS quick library, the
              size of the .QLB file may be too large to be loaded into
              the PDS environment, resulting in loading errors, in 
              which case you can only compile and link from the command
              line

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   IV.   Preparing applications for Codeview debugging 

         To build a CodeBasic application that can be debugged
         with the Codeview debugger requires the following steps:

         1. Compile one or more source modules with the /Zi switch.

         2. Link your application with the /co switch.
    
         3. If using the PDS compiler, run CVPACK on the compiled
            executable.
                                                   
         ~~~~~~~~~~~~~~~~~ END OF DOCUMENT README.DOS ~~~~~~~~~~~~~~~~~~




