Re: reading from a FIFO into a cell

[Edgar Hilton <efhilton fsmlabs com>]

Ah.  Yes, you hit it on the head.  I would be receiving either floats or
ints from a FIFO at a periodic rate: a rate which I have no way of
knowing in advance.  As the data arrives, I would need to either
recalculate the rest of the worksheet on each arrival or simply
recalculate on a slower, saner, periodic basis.  The data displayed on
the cell, however, should be "realtime".

When do you think that 2.0 will be out?

-Edgar
  


On Wed, 2001-11-14 at 10:14, Jody Goldberg wrote:
> On Tue, Nov 13, 2001 at 06:30:56PM -0500, Edgar Hilton wrote:
> > Does anybody know whether:
> >
> > 1. gnumeric allows you to read streaming data from a FIFO
> > 2. failing #1 above, would anybody know where I should look to add this
> > into the GNUMERIC source?
>
> I am not clear on what you are trying to do.  Are you trying to read
>
> a) 1 value at a time or many values
> b) What are the recalculation semantics
>
> If the goal is 1 value that will cause a complete recalc whenever
> the value changes then we do not support it now, but adding it would
> be fairly easy.  You could create a plugin (see numbertheory for an
> example) that adds 'read_fifo(fifo_name)'.  Then use g_io_add_watch 
> to register to wath the fifo for content.  This will not be as easy
> as I'd like until 2.0 because there is no easy way to manage extra
> data for each instance of a function call yet.  However, with a bit
> of creativity you should be able to do it by keeping a register of
> what has been called, and double checking that it is still there
> when data arrives.  For 2.0 I plan to extend things so that it will
> be easier to manage this sort of thing.
>
> Hope that helps
>     Jody
-- 
Edgar F. Hilton         Director of Industrial Programs
FSMLabs, Inc.           voice: (850) 322-4054
http://www.rtlinux.com  fax: (206) 350-4EFH