Re: Blocking read() from a USB->Serial adapter.

Charles Sullivan <cwsulliv@xxxxxxxxxxxx> wrote:
A blocking read() of more than one character from an actual RS232 serial
port returns when the number of characters specified has been read.

Not necessarily true.

However I've found that a blocking read() of more than one character from
a USB->Serial adapter reads only the first character before returning and
I have to loop to read all the characters.

Which makes it the same as a regular port. There may well be timing
differences though, I don't know.

I've tried this with several different USB->Serial adapters with several
different Linux kernel versions, 2.4 and 2.6, all with the same result.

Is this a Linux bug, or is there something extra I need to do in setting
up the port in my code?

Post the code you use to configure your port. It isn't really
possible to know what should be happening without looking at
what your configuration is.


--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) floyd@xxxxxxxxxx
.

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