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

On 2006-11-25, Grant Edwards <grante@xxxxxxxx> wrote:
On 2006-11-25, Floyd L. Davidson <floyd@xxxxxxxxxx> wrote:
Grant Edwards <grante@xxxxxxxx> wrote:
On 2006-11-25, Charles Sullivan <cwsulliv@xxxxxxxxxxxx> wrote:

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.

Or until the driver decides to return for whatever reason it
chooses. On success, you're guaranteed a minimum of one byte.

Maybe. (Maybe not too!)

There's the case where the file is at EOF. Is there another
case where read() will return success with 0 bytes?

AIUI EOF is not success.

a break symbol (or framing error etc...) on the seriai line
will also cause read to return.


--

Bye.
Jasen
.

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