On 07 Mar 2001 at 16:20 (-0500), Wietse Venema wrote:
| Several parts of Postfix do: connect() write() close(), where the
| close() may happen before the server has accept()ed the connection.

I see places (src/util/unix_connect.c:117) where postfix does
connect() on a non-blocking fd, tests for errno == EINPROGRESS,
then immediately returns the sockfd. I was under the impression
that when errno == EINPROGRESS, you should select()/poll() to
verify that the socket becomes writable, but I do not see where
a check for socket writability is being done before write() is
called. there is a write_wait(int,int) in postfix which looks
like it (c|sh)ould be used after connect() says EINPROGRESS
before writing.

        brent

FBSD connect(2):
     [EINPROGRESS] The socket is non-blocking and the connection cannot
                        be completed immediately. It is possible to select(2)
                        for completion by selecting the socket for writing.

Linux connect(2):
         EINPROGRESS
              The socket is non-blocking and the connection can-
              not be completed immediately. It is possible to
              select(2) or poll(2) for completion by selecting
              the socket for writing. After select indicates
              writability, use getsockopt(2) to read the SO_ERROR
              option at level SOL_SOCKET to determine whether
              connect completed successfully (SO_ERROR is zero)
              or unsuccessfully (SO_ERROR is one of the usual
              error codes listed here, explaining the reason for
              the failure).

• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]