Thanks for you help. I think i fixed it.
Andrew
Richard M. Hartman <[EMAIL PROTECTED]> wrote in message
news:19849@palm-dev-forum...
>
>
>
> Andrew Lathrop wrote in message <19835@palm-dev-forum>...
> >
> >I am using the serial manager to read in a string. I am sending the
string
> >from the palm, and reading it on the emulator. The string is stored in a
> >BytePtr array called pPointer.
>
> Assuming the declaration to be:
>
> BytePtr pPointer[n];
>
> (where 'n' is some value I have know way of knowing at this point).
>
> And there must be some sort of allocation for each slot ...
>
> int i;
> for (i=0; i<n; i++) {
> pPointer[i] = MemPtrNew(n2);
> }
>
> (where again 'n2' is some limit value I have no way of knowing)
>
> >To convert the BytePtr to a CharPtr so it
> >can be displayed using a FrmCustomAlert so i can see what data was sent.
I
> >use the following code to convert it to a CharPtr.
> > x = *pPointer[index];
>
> Given the declarations above, the you are setting 'x' to be the
> value of the first character stored, not the address of the storage
> buffer.
>
> Try
> x = pPointer[index];
> instead.
>
> (If my assumptions on your declarations are wrong, perhaps
> you could post the actual code you use...)
>
> > y = (CharPtr)*pPointer;
>
> Ok ... shouldn't 'x' be somewhere in this ?
>
> It looks like 'y' will be set to a pointer value, pointing to
> the buffer allocated for pPointer[0]; You've completely
> lost the "index" you had used in the previous line.
>
> > FrmCustomAlert( ErrorAlert, y, "", "" );
> >The problem is when i put in the FrmCustomAlert line, y changes. I don't
> >know why. Using the debugger i set a breakpoint right after the frm is
> >displayed, and it shows that x doesn't have the same value as y.
>
> This is understandable since 'x' was nowhere in the statement you
> had assigned to 'y'...
>
> >It has a
> >random character that is displayed as an outlined heart in the form.
>
> Again, according to the 'x' assigment I would expect to see a char value.
> This char should be the first char from the buffer stored at
> pPointer[index].
>
> >But
> >when i removed the FrmCustomAlert line, and use the debugger, i see that
> >both x and y have the values i expect them too.
>
> Now that I don't understand ... except that this debugger takes liberties.
> If
> optimization is turned on, the compiler might place the value in a
register
> instead of memory. In addition to that, it can reuse that register for
> another
> variable as long as the use of that value does not conflict with the first
> one.
>
> Make sure all optimizations are turned off in the compiler and try again.
>
> >The problem appears to be
> >with the FrmCustomAlert line, but have no idea why that would change the
> >value of y since it doesn't change it.
>
> It doesn't. The debugger lies to you if compiler optimizations are not
> disabled.
>
>
> --
> -Richard M. Hartman
> [EMAIL PROTECTED]
>
> 186,000 mi/sec: not just a good idea, it's the LAW!
>
>
>
>
>
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