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

On Fri, 24 Nov 2006 15:54:24 -0900, Floyd L. Davidson wrote:

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.

If that's the case, then that answers my questions. I thought blocking
meant blocking until the specified number of characters is read, or
until the read is interrupted.

Regards,
Charles Sullivan

.

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