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The Time Book sample

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Compile problems with some of the samples on the CD-ROM

• All the files have the read-only attribute set on them. If you want to load them into CodeWarrior or CodeWarrior Lite and recompile them, you'll need to copy the samples to your hard disk and reset the read-only attributes. You can do this from Explorer using the Properties item in the popup menu, but it's a pain to do this for each file. A simpler solution is to open a DOS box, change to the appropriate directory, and run the command "attrib -r *.*" instead. Or you can download the corrected samples as described below.
• CodeWarrior Lite Release 5, which is the version included on the CD-ROM, has limits on the size of code segments and on the number of code segments which means that it can't link the larger samples. Note that you can still use CW Lite to look at the code for each sample and you can also run each sample because a pre-built .prc file is included for each sample. If you want to compile these samples, you'll need to get CodeWarrior Lite Release 6 from the Metrowerks website and download updated samples.

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Updated samples for Release 6 of CodeWarrior and CodeWarrior Lite

ftp://ftp.ericgiguere.com/pub/palmbook/cdrom/R6Samples.zip

CodeWarrior Lite users: You can download Release 6 of CodeWarrior Lite from the Metrowerks ftp site:

ftp://ftp2.metrowerks.com/pub/tools/lite/PalmComputing/cw_lite_palm_win.exe

This version of CodeWarrior Lite is less restrictive than Release 5, but it is missing the library files that are necessary to build C++ programs. Since the samples require C++, you have to copy some files from Release 5 over to Release 6. Here's what you do:

• Install CodeWarrior Lite Release 5. You'll find the installation program on your CD-ROM in the "Evaluation Software" folder. Say you install Release 5 to the directory C:\CWLiteR5.
• Install CodeWarrior Lite Release 6 in a different directory, say C:\CWLiteR6.
• Open the "Palm OS 3.0 Support" folder in C:\CWLiteR5.
• Open the "Palm OS 3.1 Support" folder in C:\CWLiteR6.
• Note how the "Runtime" folder in "Palm OS 3.0 Support" is missing from "Palm OS 3.1 Support". Copy it over.

If you'd rather use a DOS shell, just do:

    cd "c:\CWLiteR6\Palm OS 3.1 Support"
    xcopy "c:\CWLiteR5\Palm OS 3.0 Support\Runtime" Runtime

You should now be able to build and link all the samples using CodeWarrior Lite Release 6.

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Corrected CD-ROM contents

ftp://ftp.ericgiguere.com/pub/palmbook/cdrom

You'll see the same set of folders that are on the CD-ROM. You can navigate through the folders and download any of the files that interest you. Note that due to licensing restrictions the Evaluation Software and Palm Computing folders are empty -- you'll have to get the software and documentation in those folders from the original CD-ROM or download them from the appropriate websites.

If you can't access the CD-ROM image for some reason, send me mail at ericgiguere@ericgiguere.com and I can mail the files to you.

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Relaunching a program may require a new stack

The RelaunchWithGlobals function described in Chapter 4 (in the section "Recovering Global Data") neglected to allocate a new stack when it relaunched the application. This may cause the relaunched application to terminate due to a stack fault if your application does a lot of recursion or allocates large objects on the stack. The solution is simple, just add the sysAppLaunchFlagNewStack flag as follows:

// Relaunches an application with globals enabled.
//    creatorID -- the creatorID of the application
//    cmd       -- the launch code
//    cmdPBP    -- the launch parameter block
//    ret       -- holds the return value after the launch
// Returns: non-zero if the launch failed

Err RelaunchWithGlobals( ULong creatorID, Word cmd,
                         Ptr cmdPBP, DWord *ret )
{
    UInt              card;
    LocalID           id;
    Err               err = sysErrNotAllowed;
    DmSearchStateType stateInfo;

    if( DmGetNextDatabaseByTypeCreator( true, &stateInfo,
                                        'appl', creatorID,
                                        true, &card, &id ) == 0 ){
        err = SysAppLaunch( card, id,
                            sysAppLaunchFlagNewGlobals  | sysAppLaunchFlagNewStack,
			    cmd, cmdPBP, ret );
    }

    return err;
}

Of course, there's a trade-off involved here because each time you allocate a new stack you lose 2K from dynamic memory. Experiment with the flag and see what's right for your application, although in most cases you'll probably want to have it on, because you really never know how much stack space is available when your application is called in a non-initializing launch. The samples on the CD-ROM (which were finished after the book text) use this flag, for example.

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The wrong syntax is used to access field names in the Consolidator

    olrl4p_tEMPLOYEE_Fields::ix_Name

    olrl4p_tEMPLOYEE_Record::ix_Name

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