listen - listen for connections on a socket
int s, backlog;
To accept connections, a socket is first created with socket(2), a willingness to accept
incoming connections and a queue limit for incoming connections are specified with lis-
ten(2), and then the connections are accepted with accept(2). The listen call applies
only to sockets of type SOCK_STREAM or SOCK_SEQPACKET.
The backlog 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 retransmis-
sion, the request may be ignored so that retries may succeed.
A 0 return value indicates success; -1 indicates an error.
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 operation listen.
SEE ALSOaccept(2), connect(2), socket(2)BUGS
The backlog is currently limited (silently) to 5.
4.2 Berkeley Distribution May 14, 1986 LISTEN(2)