On Iau, 2004-11-18 at 03:42, James Morris wrote:
> > Well, my reading of socket(2) suggests that it's _not_ supposed to work.
> sendto() on a non connected socket should fail with ENOTCONN.
Not entirely true at all. A network protocol can implement lazy binding
do implicit binding on the sendto. Other protocols might not actually
a receiving component so have no bind() functionality at all.
> According to the send(2) man page, we may return EISCONN if the address
> and addr length are not NULL and zero. I think that the man page is
> incorrect. Posix says that EISCONN means "A destination address was
> specified and the socket is already connected", not "A destination address
> was specified and the socket is connected mode". i.e. we should only
> return EISCONN if the socket is in a connected state.
POSIX 1003.1g draft 6.4 permits a user to pass a "null" address for
various things. Indeed some systems implement send() as sendto() with a
NULL, 0 address component and some user space does likewise. It also has
a lot to say on the other cases although I don't think it ever fully got
past draft state.
You also want to look at TCP/IP illustrated to see some of the
assumptions handed down from on high by BSD and which should not be