LISTEN(2) 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 incom‐ ing 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 ECON‐ NREFUSED, 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 descriptor. [ENOTSOCK] The argument _s is not a socket. [EOPNOTSUPP] The socket is not of a type that supports the oper‐ ation _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. 4.2 Berkeley Distribution May 14, 1986 LISTEN(2)