Maybe there is a padding byte between the ttype and seconds,
so the struct you are using, is treated by the compiler (in order to
preserve 2byte aligment) like this:
typedef struct FuelsDBType
{
char ttype;
------- char padding;---------
UInt32 seconds; // Timestamp
char tailno[9];
char amount[11];
} FuelsDBType;
----- Original Message -----
From: "Ray Marron" <[EMAIL PROTECTED]>
Newsgroups: palm-dev-forum
To: "Palm Developer Forum" <[EMAIL PROTECTED]>
Sent: Monday, February 17, 2003 19:12
Subject: Prob reading uint32 from db
> I added a UInt32 value in my Palm app's database to act as a timestamp
that
> gets its value from TimGetSeconds() just before the record is saved. When
I
> read this value back out, it is always a much smaller value. I'm sure I'm
> messing it up during the save or retrieval. Can somebody take a look at
my
> code and see if you can notice anything I'm doing wrong? This is my first
> Palm app, and most of my save/load code was taken from CW and book
examples.
> If there is some code you would like to see that I haven't included, just
> request it.
>
> For example, if I save a record with a timestamp of 3128320727 (the
morning
> of 2003-02-17), it gets read back as 1985899456 (sometime in 1966!).
There
> doesn't seem to be a constant difference between the saved/read values,
but
> the difference is always ~1.141 billion.
>
> Pasted from my app's header file:
>
> typedef struct FuelsDBType
> {
> char ttype;
> UInt32 seconds; // Timestamp
> char tailno[9];
> char amount[11];
> } FuelsDBType;
>
> typedef FuelsDBType* FuelsDBPtr;
>
> #define FDB_TTYPE_START 0
> #define FDB_TTYPE_SIZE sizeof(char)
> #define FDB_SECONDS_START (FDB_TTYPE_START + FDB_TTYPE_SIZE)
> #define FDB_SECONDS_SIZE sizeof(UInt32)
> #define FDB_TAILNO_START (FDB_SECONDS_START + FDB_SECONDS_SIZE)
> #define FDB_TAILNO_SIZE 9
> #define FDB_AMOUNT_START (FDB_TAILNO_START + FDB_TAILNO_SIZE)
> #define FDB_AMOUNT_SIZE 11
>
> #define FDB_RECSIZE (FDB_AMOUNT_START + FDB_AMOUNT_SIZE)
>
> The seconds value was formerly at the end of the struct. I moved it up
> behind ttype in case my string saving was buggy but it didn't change
> anything.
>
> From my app's database.c:
>
> Err AddToDatabase(FuelsDBPtr recordP)
> {
> Err error = errNone;
> UInt16 recIndex = dmMaxRecordIndex;
> MemHandle recH;
> MemPtr recP;
>
> recH = DmNewRecord(gDB, &recIndex, FDB_RECSIZE);
> if (recH) {
> recP = MemHandleLock(recH);
> DmWrite(recP, FDB_TTYPE_START, &recordP->ttype,
> FDB_TTYPE_SIZE);
> DmWrite(recP, FDB_SECONDS_START, &recordP->seconds,
> FDB_SECONDS_SIZE);
> DmWrite(recP, FDB_TAILNO_START, recordP->tailno,
> FDB_TAILNO_SIZE);
> DmWrite(recP, FDB_AMOUNT_START, recordP->amount,
> FDB_AMOUNT_SIZE);
> error = DmReleaseRecord(gDB, recIndex, true);
> MemHandleUnlock(recH);
> }
>
> if (error == errNone)
> return 0;
> else
> return DmGetLastErr();
> }
>
>
> Err GetFromDatabase(FuelsDBPtr recordP, UInt32 cursor)
> {
> MemHandle recH;
> FuelsDBPtr recP;
> Err error = 0;
>
> recH = DmQueryRecord(gDB, cursor);
> if (recH)
> {
> recP = (FuelsDBPtr)MemHandleLock(recH);
> recordP->ttype = recP->ttype;
> recordP->seconds = recP->seconds;
> StrCopy(recordP->tailno, recP->tailno);
> StrCopy(recordP->amount, recP->amount);
> MemHandleUnlock(recH);
> }
> else
> error = DmGetLastErr();
> return error;
> }
>
> Thanks for your help!
>
> --
> Ray Marron
>
>
>
> --
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