Re: Advice on abort

["REH" <me@you.com>]

"Simon Wright" <simon@pushface.org> wrote in message 
news:m2fyqb9c6o.fsf@grendel.local...
> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:
>
>> Close that socket from another task. That should end the blocking
>> I/O on the socket with some error code. And the task will become
>> ready accept a rendezvous.
>
> We have recently been bitten by OS-dependent behaviour in this area.
>
> On Windows, the read fails immediately with an
> GNAT.Sockets.Socket_Error exception. However, on VxWorks and Linux
> (and possibly other OS's), you get a successful read of *zero* bytes
> (at any rate, fewer than you requested) and the exception only happens
> on the next read.
>
> Of course, getting a short read may end up with an
> Ada.IO_Exceptions.End_Error anyway (we had forgotten to check the
> length :-( ).

That's fine.  We are VxWorks too.  Besides, a return of 0 on a read is not 
considered "successful" with sockets.  It means the socket has been closed. 
You got an exception on the next read, because you were trying to read from 
a closed socket.

REH