4.3BSD-UWisc/man/cat2/listen.2

LISTEN(2)           UNIX Programmer's Manual            LISTEN(2)



NAME
     listen - listen for connections on a socket

SYNOPSIS
     listen(s, backlog)
     int s, backlog;

DESCRIPTION
     To accept connections, a socket is first created with
     _s_o_c_k_e_t(2), a willingness to accept incoming connections and
     a queue limit for incoming connections are specified with
     _l_i_s_t_e_n(2), and then the connections are accepted with
     _a_c_c_e_p_t(2).  The _l_i_s_t_e_n call applies only to sockets of type
     SOCK_STREAM or SOCK_SEQPACKET.

     The _b_a_c_k_l_o_g parameter defines the maximum length the queue
     of pending connections may grow to.  If a connection request
     arrives with the queue full the client may receive an error
     with an indication of ECONNREFUSED, or, if the underlying
     protocol supports retransmission, the request may be ignored
     so that retries may succeed.

RETURN VALUE
     A 0 return value indicates success; -1 indicates an error.

ERRORS
     The call fails if:

     [EBADF]             The argument _s is not a valid descrip-
                         tor.

     [ENOTSOCK]          The argument _s is not a socket.

     [EOPNOTSUPP]        The socket is not of a type that sup-
                         ports the operation _l_i_s_t_e_n.

SEE ALSO
     accept(2), connect(2), socket(2)

BUGS
     The _b_a_c_k_l_o_g is currently limited (silently) to 5.














Printed 12/27/86          May 14, 1986                          1