Good point...and since we're providing a DA-like hack,
e.g., which could cause a MemoPad record to be updated
while one is updating a MemoPad record using MemoPad,
we really should take care of this.

Thanks for all the replies!  Joe

"Richard M. Hartman" <[EMAIL PROTECTED]> wrote in message
news:89900@palm-dev-forum...
>
> Currently there is little danger in not locking the record.  The
> OS is not multitasking, so no other program should be attempting
> to access it at the same time (there are, however, hacks, DAs
> & other such exceptions to be considered).
>
> Once a real multitasking OS becomes available, record
> locking will be much more important.  May as well write your
> code the right way now, and avoid pain later.
>
> --
> -Richard M. Hartman
> [EMAIL PROTECTED]
>
> 186,000 mi/sec: not just a good idea, it's the LAW!
>
> "Danny Epstein" <[EMAIL PROTECTED]> wrote in message
> news:89795@palm-dev-forum...
> >
> > > It seems like a bad idea, but
> > > what are the implications of modifying a db record that was
> > > accessed via DmQueryRecord versus DmGetRecord?
> >
> > I agree, in general. However, ISTR that some of our example code does
> this.
> >
> > > I was surprised to discover that I can actually modify
> > > a record that was accessed with DmQueryRecord,
> > > and I'm wondering in what situations this is actually ok,
> > > since DmQueryRecord is much faster than DmGetRecord.
> >
> > Yup. The OS doesn't enforce the rule that records must be marked busy
> before
> > being modified. The APIs for modifying a record's contents take a
pointer
> to
> > the record contents rather than a record number. This would make it
> > difficult to verify that the busy bit is set without support from the
> memory
> > manager.
> >
> > In general, if you're going to modify a record, you probably want to set
> the
> > dirty bit. Passing true to DmReleaseRecord is a convenient way to do
this.
> >
> > My take on it is that the busy bit is primarily used to prevent
> programming
> > errors. I generally use DmGetRecord if I'm going to modify a record.
I've
> > made exceptions when building abstraction layers where it's inconvenient
> to
> > distinguish between reading and writing.
> > --
> > Danny @ PalmSource
> >
> >
>
>
>
>



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