ERRORS
     The connect() system call fails if:

     [EBADF]            The s argument is not a valid descriptor.

     [EINVAL]           The namelen argument is not a valid length for the
                        address family.

     [ENOTSOCK]         The s argument is a descriptor for a file, not a
                        socket.

     [EADDRNOTAVAIL]    The specified address is not available on this
                        machine.

     [EAFNOSUPPORT]     Addresses in the specified address family cannot be
                        used with this socket.

     [EISCONN]          The socket is already connected.

     [ETIMEDOUT]        Connection establishment timed out without
                        establishing a connection.

     [ECONNREFUSED]     The attempt to connect was forcefully rejected.

     [ECONNRESET]       The connection was reset by the remote host.

     [ENETUNREACH]      The network is not reachable from this host.

     [EHOSTUNREACH]     The remote host is not reachable from this host.

     [EADDRINUSE]       The address is already in use.

     [EFAULT]           The name argument specifies an area outside the
                        process address space.

     [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.

     [EINTR]            The connection attempt was interrupted by the delivery
                        of a signal.  The connection will be established in
                        the background, as in the case of EINPROGRESS.

     [EALREADY]         A previous connection attempt has not yet been
                        completed.

     [EACCES]           An attempt is made to connect to a broadcast address
                        (obtained through the INADDR_BROADCAST constant or the
                        INADDR_NONE return value) through a socket that does
                        not provide broadcast functionality.

     [EAGAIN]           An auto-assigned port number was requested but no
                        auto-assigned ports are available.  Increasing the
                        port range specified by sysctl(3) MIB variables
                        net.inet.ip.portrange.first and
                        net.inet.ip.portrange.last may alleviate the problem.

     The following errors are specific to connecting names in the UNIX domain.
     These errors may not apply in future versions of the UNIX IPC domain.

     [ENOTDIR]          A component of the path prefix is not a directory.

     [ENAMETOOLONG]     A component of a pathname exceeded 255 characters, or
                        an entire path name exceeded 1023 characters.

     [ENOENT]           The named socket does not exist.

     [EACCES]           Search permission is denied for a component of the
                        path prefix.

     [EACCES]           Write access to the named socket is denied.

     [ELOOP]            Too many symbolic links were encountered in
                        translating the pathname.

     [EPERM]            Write access to the named socket is denied.