Re: streaming buffer question

On Tue, 12 Nov 2002, David Schleef wrote:

> On Tue, Nov 12, 2002 at 02:31:40PM -0700, Jim Benson wrote:
> 
> > If i read say the first 500 bytes and then mark that
> > read as read with comedi_mark_buffer_read...
> 
> Don't do this.  Just read() the samples as if it were a file
> or network socket.  See the demo/cmd.c example.
> 
 
Thanks...i did look at that example first...before
i switched to the mmap example. I'm guessing that
using a memory map will ultimately give a faster
"read" than using something like:

read(comedi_fileno(dev), buf, BUFSZ);

Then i started trying to figure out
what happens when the streaming buffer fills up...
or even what happens when i read n bytes
of N (n < N) available. Then, once it fills 
up, what action do i do that effectively tells
comedi that it can start filling the streaming 
buffer at some start offset. 

I'm probably making this more complicated
than it is.

Thanks,

Jim

Received on 2002-11-12Z22:32:26