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LISTEN(2)		  FreeBSD System Calls Manual		     LISTEN(2)

NAME
     listen -- listen for connections on a socket

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <sys/socket.h>

     int
     listen(int	s, int backlog);

DESCRIPTION
     To	accept connections, a socket is	first created with socket(2), a	will-
     ingness to	accept incoming	connections and	a queue	limit for incoming
     connections are specified with listen(), and then the connections are ac-
     cepted 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 retransmission, the request may
     be	ignored	so that	retries	may succeed.

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

ERRORS
     listen() will fail	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 opera-
			tion listen().

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

HISTORY
     The listen() function call	appeared in 4.2BSD.

BUGS
     The backlog is currently limited (silently) to 128.

FreeBSD	13.0		       December	11, 1993		  FreeBSD 13.0

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | HISTORY | BUGS

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