Okay I've figured out a way around this issue but I still have no idea why
exactly it's occuring. First of all "p" from the code below is declared as
MemPtr *. If I declare a char * and use the following code instead of "p +=
sizeof(UrlRecord)", my app works properly:
cTemp = (char * ) p;
cTemp += sizeof(UrlRecord);
p = (MemPtr * ) cTemp;
It looks like even though the size of a UrlRecord is the same between the
two apps, doing "p += sizeof(UrlRecord)" actually increments the pointer too
far. Is this because I'm working with a MemPtr * instead of just a MemPtr?
I tried starting off with just a plain MemPtr but the "p +=" code throws a
compiler error in this case.
"Mark Biek" <[EMAIL PROTECTED]> wrote in message
news:82163@palm-dev-forum...
>
> I have one application that creates a database. Each record in the
database
> is made up of these two structures:
>
> typedef struct FormProperty
> {
> char propertyName[50];w
> char propertyValue[255];
> int x;
> int y;
> int w;
> int h;
> }FormProperty;
>
> typedef struct UrlRecord
> {
> char url[255];
> int numProps;
> }UrlRecord;
>
> Basically the record form is <UrlRecord><FormProperty><FormProperty> with
an
> arbitrary number of form properties. I have a whole set of functions for
> reading and writing these records and they all work nicely in the main
> application which creates the database.
>
> The problem I'm having now is that I have a second application that needs
to
> read these same functions so I've copied code from the first application
but
> it doesn't seem to be working.
>
> In order to read through each record I do something like the following:
>
> h = DmQueryRecord(dbPrefs,urlIndex);
> p = MemHandleLock(h);
>
> //The first item in the record is a UrlRecord object
> urlRec=( UrlRecord *) p;
>
> //Move on the first FormProperty
> p += sizeof(UrlRecord);
> formProp= (FormProperty *) p;
>
> The portion of the code where I read the UrlRecord works in the second
> application but I get garbage when I increment the pointer to the
> FormProperty part of the record.
>
> Does anyone have any ideas why this might happen? Thanks
>
> Mark
>
>
>
>
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