[En-Nut-Discussion] Maybe obvious ...

Nathan Moore nategoose at gmail.com
Sun Nov 15 21:09:56 CET 2009

Hey Rob,

On Sun, Nov 15, 2009 at 6:26 AM, Rob van Lieshout (PragmaLab) <
info at pragmalab.nl> wrote:

> Please be aware that in the end 'fprint' is using IO to print the message
> (normally the UART will be used for that). So in other words, this fprintf
> statement might end up in a NutThreadYield() as well... If there's enough
> space in the IO-buffer (driver) to send the message in 1 piece, the thread
> will not be yielded, if not, the thread is yielded and is set running again
> by the driver as soon as its buffer has space available.....

That's sort of what I what I was trying to say, but fprintf doesn't have to
any actual IO (in ram filesystem or null dev), could do non-blocking IO, or
could use polling IO (avr's debug uart), all of which won't require a
(thread) switch.


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