POSIX Networking option group. More...

Files
file	inet.h
	Internet address conversion functions (<arpa/inet.h>)

file	if.h
	Network interface names and indices (<net/if.h>)

file	netdb.h
	POSIX network database operations (<netdb.h>)

file	in.h
	Internet address types and constants (<netinet/in.h>)

file	tcp.h
	TCP definitions (<netinet/tcp.h>)

file	socket.h
	POSIX socket API (<sys/socket.h>)

file	un.h
	POSIX UNIX domain socket types (<sys/un.h>)

Functions
in_addr_t	inet_addr (const char *cp)
	Convert an IPv4 address from dotted-decimal text to binary.

char *	inet_ntoa (struct in_addr in)
	Convert an IPv4 address from binary to dotted-decimal text.

char *	inet_ntop (sa_family_t family, const void src, char dst, size_t size)
	Convert an IPv4 or IPv6 address from binary to text form.

int	inet_pton (sa_family_t family, const char src, void dst)
	Convert an IPv4 or IPv6 address from text form to binary.

char *	if_indextoname (unsigned int ifindex, char *ifname)
	Map a network interface index to its name.

void	if_freenameindex (struct if_nameindex *ptr)
	Free a list returned by if_nameindex().

struct if_nameindex *	if_nameindex (void)
	Return all network interfaces as a name-index array.

unsigned int	if_nametoindex (const char *ifname)
	Map a network interface name to its index.

void	endhostent (void)
	Close the hosts database.

void	endnetent (void)
	Close the networks database.

void	endprotoent (void)
	Close the protocols database.

void	endservent (void)
	Close the services database.

void	freeaddrinfo (struct addrinfo *ai)
	Free addrinfo list returned by getaddrinfo.

const char *	gai_strerror (int errcode)
	Return a string describing a getaddrinfo error code.

int	getaddrinfo (const char host, const char service, const struct addrinfo hints, struct addrinfo *res)
	Translate a hostname and service to a list of socket addresses.

struct hostent *	gethostent (void)
	Get the next entry from the hosts database.

int	getnameinfo (const struct sockaddr addr, socklen_t addrlen, char host, socklen_t hostlen, char *serv, socklen_t servlen, int flags)
	Translate a socket address to a hostname and service name.

struct netent *	getnetbyaddr (uint32_t net, int type)
	Look up a network by address.

struct netent *	getnetbyname (const char *name)
	Look up a network by name.

struct netent *	getnetent (void)
	Get the next entry from the networks database.

struct protoent *	getprotobyname (const char *name)
	Look up a protocol by name.

struct protoent *	getprotobynumber (int proto)
	Look up a protocol by number.

struct protoent *	getprotoent (void)
	Get the next entry from the protocols database.

struct servent *	getservbyname (const char name, const char proto)
	Look up a service by name and protocol.

struct servent *	getservbyport (int port, const char *proto)
	Look up a service by port number and protocol.

struct servent *	getservent (void)
	Get the next entry from the services database.

void	sethostent (int stayopen)
	Open the hosts database.

void	setnetent (int stayopen)
	Open the networks database.

void	setprotoent (int stayopen)
	Open the protocols database.

void	setservent (int stayopen)
	Open the services database.

int	accept (int sock, struct sockaddr addr, socklen_t addrlen)
	Accept a new connection on a listening socket.

int	bind (int sock, const struct sockaddr *addr, socklen_t addrlen)
	Assign a local address to a socket.

int	connect (int sock, const struct sockaddr *addr, socklen_t addrlen)
	Initiate a connection on a socket.

int	getpeername (int sock, struct sockaddr addr, socklen_t addrlen)
	Get the address of the peer connected to a socket.

int	getsockname (int sock, struct sockaddr addr, socklen_t addrlen)
	Get the local address bound to a socket.

int	getsockopt (int sock, int level, int optname, void optval, socklen_t optlen)
	Get socket options.

int	listen (int sock, int backlog)
	Mark a socket as passive (ready to accept connections).

ssize_t	recv (int sock, void *buf, size_t max_len, int flags)
	Receive data from a connected socket.

ssize_t	recvfrom (int sock, void buf, size_t max_len, int flags, struct sockaddr src_addr, socklen_t *addrlen)
	Receive data and the sender's address from a socket.

ssize_t	recvmsg (int sock, struct msghdr *msg, int flags)
	Receive a message (with scatter-gather I/O and ancillary data).

ssize_t	send (int sock, const void *buf, size_t len, int flags)
	Send data on a connected socket.

ssize_t	sendmsg (int sock, const struct msghdr *message, int flags)
	Send a message (with scatter-gather I/O and ancillary data).

ssize_t	sendto (int sock, const void buf, size_t len, int flags, const struct sockaddr dest_addr, socklen_t addrlen)
	Send data to a specific destination address.

int	setsockopt (int sock, int level, int optname, const void *optval, socklen_t optlen)
	Set socket options.

int	shutdown (int sock, int how)
	Shut down part or all of a full-duplex connection.

int	sockatmark (int s)
	Determine whether a socket is at the out-of-band mark.

int	socket (int family, int type, int proto)
	Create a new socket.

int	socketpair (int family, int type, int proto, int sv[2])
	Create a pair of connected sockets.

int	gethostname (char *name, size_t namelen)
	Get the name of the current host.

Detailed Description

POSIX Networking option group.

Function Documentation

◆ accept()

int accept	(	int	sock,
		struct sockaddr *	addr,
		socklen_t *	addrlen
	)

Accept a new connection on a listening socket.

Parameters

sock	Listening socket file descriptor.
addr	Output: address of the connecting peer, or `NULL`.
addrlen	Input: size of `addr`; output: actual address size.

Returns: New socket file descriptor on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/accept.html

◆ bind()

int bind	(	int	sock,
		const struct sockaddr *	addr,
		socklen_t	addrlen
	)

Assign a local address to a socket.

Parameters

sock	Socket file descriptor.
addr	Local address to bind.
addrlen	Size of `addr` in bytes.

Returns: 0 on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/bind.html

◆ connect()

int connect	(	int	sock,
		const struct sockaddr *	addr,
		socklen_t	addrlen
	)

Initiate a connection on a socket.

Parameters

sock	Socket file descriptor.
addr	Remote address to connect to.
addrlen	Size of `addr` in bytes.

Returns: 0 on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/connect.html

◆ endhostent()

void endhostent ( void )

Close the hosts database.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/endhostent.html

◆ endnetent()

void endnetent ( void )

Close the networks database.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/endnetent.html

◆ endprotoent()

void endprotoent ( void )

Close the protocols database.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/endprotoent.html

◆ endservent()

void endservent ( void )

Close the services database.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/endservent.html

◆ freeaddrinfo()

void freeaddrinfo ( struct addrinfo * ai )

Free addrinfo list returned by getaddrinfo.

Parameters

ai	Linked list to free.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/freeaddrinfo.html

◆ gai_strerror()

const char * gai_strerror ( int errcode )

Return a string describing a getaddrinfo error code.

Parameters

errcode Error code returned by getaddrinfo.

Returns: Pointer to a description string.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/gai_strerror.html

◆ getaddrinfo()

int getaddrinfo	(	const char *	host,
		const char *	service,
		const struct addrinfo *	hints,
		struct addrinfo **	res
	)

Translate a hostname and service to a list of socket addresses.

Parameters

host	Hostname or numeric address string, or `NULL`.
service	Service name or numeric port string, or `NULL`.
hints	Criteria for address selection, or `NULL` for defaults.
res	Output: linked list of matching addresses.

Returns: 0 on success, or a non-zero EAI_* error code.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getaddrinfo.html

◆ gethostent()

struct hostent * gethostent ( void )

Get the next entry from the hosts database.

Returns: Pointer to a static hostent on success, or NULL at end or on error.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/gethostent.html

◆ gethostname()

int gethostname	(	char *	name,
		size_t	namelen
	)

Get the name of the current host.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/gethostname.html

◆ getnameinfo()

int getnameinfo	(	const struct sockaddr *	addr,
		socklen_t	addrlen,
		char *	host,
		socklen_t	hostlen,
		char *	serv,
		socklen_t	servlen,
		int	flags
	)

Translate a socket address to a hostname and service name.

Parameters

addr	Socket address to look up.
addrlen	Size of `addr`.
host	Output buffer for the hostname, or `NULL`.
hostlen	Size of `host`.
serv	Output buffer for the service name, or `NULL`.
servlen	Size of `serv`.
flags	NI_* flags controlling the conversion.

Returns: 0 on success, or a non-zero EAI_* error code.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getnameinfo.html

◆ getnetbyaddr()

struct netent * getnetbyaddr	(	uint32_t	net,
		int	type
	)

Look up a network by address.

Parameters

net	Network number (host byte order).
type	Address type (AF_INET).

Returns: Pointer to a static netent, or NULL on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getnetbyaddr.html

◆ getnetbyname()

struct netent * getnetbyname ( const char * name )

Look up a network by name.

Parameters

name	Network name.

Returns: Pointer to a static netent, or NULL on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getnetbyname.html

◆ getnetent()

struct netent * getnetent ( void )

Get the next entry from the networks database.

Returns: Pointer to a static netent, or NULL at end or on error.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getnetent.html

◆ getpeername()

int getpeername	(	int	sock,
		struct sockaddr *	addr,
		socklen_t *	addrlen
	)

Get the address of the peer connected to a socket.

Parameters

sock	Socket file descriptor.
addr	Output: peer address.
addrlen	Input: size of `addr`; output: actual size.

Returns: 0 on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getpeername.html

◆ getprotobyname()

struct protoent * getprotobyname ( const char * name )

Look up a protocol by name.

Parameters

name	Protocol name (e.g. `"tcp"`).

Returns: Pointer to a static protoent, or NULL on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getprotobyname.html

◆ getprotobynumber()

struct protoent * getprotobynumber ( int proto )

Look up a protocol by number.

Parameters

proto Protocol number.

Returns: Pointer to a static protoent, or NULL on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getprotobynumber.html

◆ getprotoent()

struct protoent * getprotoent ( void )

Get the next entry from the protocols database.

Returns: Pointer to a static protoent, or NULL at end or on error.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getprotoent.html

◆ getservbyname()

struct servent * getservbyname	(	const char *	name,
		const char *	proto
	)

Look up a service by name and protocol.

Parameters

name	Service name (e.g. `"http"`).
proto	Protocol (`"tcp"`, `"udp"`, or `NULL` for any).

Returns: Pointer to a static servent, or NULL on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getservbyname.html

◆ getservbyport()

struct servent * getservbyport	(	int	port,
		const char *	proto
	)

Look up a service by port number and protocol.

Parameters

port	Port number (network byte order).
proto	Protocol (`"tcp"`, `"udp"`, or `NULL` for any).

Returns: Pointer to a static servent, or NULL on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getservbyport.html

◆ getservent()

struct servent * getservent ( void )

Get the next entry from the services database.

Returns: Pointer to a static servent, or NULL at end or on error.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getservent.html

◆ getsockname()

int getsockname	(	int	sock,
		struct sockaddr *	addr,
		socklen_t *	addrlen
	)

Get the local address bound to a socket.

Parameters

sock	Socket file descriptor.
addr	Output: local address.
addrlen	Input: size of `addr`; output: actual size.

Returns: 0 on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getsockname.html

◆ getsockopt()

int getsockopt	(	int	sock,
		int	level,
		int	optname,
		void *	optval,
		socklen_t *	optlen
	)

Get socket options.

Parameters

sock	Socket file descriptor.
level	Protocol level (SOL_SOCKET, IPPROTO_TCP, etc.).
optname	Option name (SO_REUSEADDR, SO_KEEPALIVE, etc.).
optval	Output: option value.
optlen	Input: size of `optval`; output: actual size.

Returns: 0 on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getsockopt.html

◆ if_freenameindex()

void if_freenameindex ( struct if_nameindex * ptr )

Free a list returned by if_nameindex().

Parameters

ptr	List to free (must have been returned by if_nameindex()).

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/if_freenameindex.html

◆ if_indextoname()

char * if_indextoname	(	unsigned int	ifindex,
		char *	ifname
	)

Map a network interface index to its name.

Parameters

ifindex	Numeric interface index.
ifname	Output buffer of at least IF_NAMESIZE bytes.

Returns: ifname on success, or NULL with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/if_indextoname.html

◆ if_nameindex()

struct if_nameindex * if_nameindex ( void )

Return all network interfaces as a name-index array.

The returned array is terminated by an entry with if_index == 0 and if_name == NULL. Free with if_freenameindex().

Returns: Allocated array on success, or NULL with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/if_nameindex.html

◆ if_nametoindex()

unsigned int if_nametoindex ( const char * ifname )

Map a network interface name to its index.

Parameters

ifname Interface name string.

Returns: Interface index on success, or 0 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/if_nametoindex.html

◆ inet_addr()

in_addr_t inet_addr ( const char * cp )

Convert an IPv4 address from dotted-decimal text to binary.

Note: Deprecated; use inet_pton() for new code.

Parameters

cp	Dotted-decimal IPv4 address string (e.g. "192.0.2.1").

Returns: IPv4 address in network byte order, or (in_addr_t)(-1) on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/inet_addr.html

◆ inet_ntoa()

char * inet_ntoa ( struct in_addr in )

Convert an IPv4 address from binary to dotted-decimal text.

Note: Deprecated; use inet_ntop() for new code. The returned pointer is to a static buffer that may be overwritten by subsequent calls.

Parameters

in	IPv4 address in network byte order.

Returns: Pointer to a dotted-decimal string, or NULL on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/inet_ntoa.html

◆ inet_ntop()

char * inet_ntop	(	sa_family_t	family,
		const void *	src,
		char *	dst,
		size_t	size
	)

Convert an IPv4 or IPv6 address from binary to text form.

Parameters

family	Address family: AF_INET or AF_INET6.
src	Source address in network byte order.
dst	Output buffer for the text form.
size	Size of `dst` in bytes (`INET_ADDRSTRLEN` / `INET6_ADDRSTRLEN`).

Returns: dst on success, or NULL with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/inet_ntop.html

◆ inet_pton()

int inet_pton	(	sa_family_t	family,
		const char *	src,
		void *	dst
	)

Convert an IPv4 or IPv6 address from text form to binary.

Parameters

family	Address family: AF_INET or AF_INET6.
src	Text form of the address.
dst	Output buffer for the binary address.

Returns: 1 on success, 0 if src is not a valid address, or -1 with errno set on error.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/inet_pton.html

◆ listen()

int listen	(	int	sock,
		int	backlog
	)

Mark a socket as passive (ready to accept connections).

Parameters

sock	Socket file descriptor.
backlog	Maximum number of pending connections to queue.

Returns: 0 on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/listen.html

◆ recv()

ssize_t recv	(	int	sock,
		void *	buf,
		size_t	max_len,
		int	flags
	)

Receive data from a connected socket.

Parameters

sock	Socket file descriptor.
buf	Buffer to receive data into.
max_len	Maximum number of bytes to receive.
flags	`MSG_*` flags (MSG_PEEK, MSG_WAITALL, etc.).

Returns: Number of bytes received, 0 on connection closed, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/recv.html

◆ recvfrom()

ssize_t recvfrom	(	int	sock,
		void *	buf,
		size_t	max_len,
		int	flags,
		struct sockaddr *	src_addr,
		socklen_t *	addrlen
	)

Receive data and the sender's address from a socket.

Parameters

sock	Socket file descriptor.
buf	Buffer to receive data into.
max_len	Maximum number of bytes to receive.
flags	MSG_* flags.
src_addr	Output: sender's address, or `NULL`.
addrlen	Input: size of `src_addr`; output: actual size.

Returns: Number of bytes received on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/recvfrom.html

◆ recvmsg()

ssize_t recvmsg	(	int	sock,
		struct msghdr *	msg,
		int	flags
	)

Receive a message (with scatter-gather I/O and ancillary data).

Parameters

sock	Socket file descriptor.
msg	Message header specifying I/O vectors and address buffer.
flags	MSG_* flags.

Returns: Number of bytes received on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/recvmsg.html

◆ send()

ssize_t send	(	int	sock,
		const void *	buf,
		size_t	len,
		int	flags
	)

Send data on a connected socket.

Parameters

sock	Socket file descriptor.
buf	Data to send.
len	Number of bytes to send.
flags	`MSG_*` flags (MSG_OOB, MSG_NOSIGNAL, etc.).

Returns: Number of bytes sent on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/send.html

◆ sendmsg()

ssize_t sendmsg	(	int	sock,
		const struct msghdr *	message,
		int	flags
	)

Send a message (with scatter-gather I/O and ancillary data).

Parameters

sock	Socket file descriptor.
message	Message header specifying I/O vectors and destination.
flags	MSG_* flags.

Returns: Number of bytes sent on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/sendmsg.html

◆ sendto()

ssize_t sendto	(	int	sock,
		const void *	buf,
		size_t	len,
		int	flags,
		const struct sockaddr *	dest_addr,
		socklen_t	addrlen
	)

Send data to a specific destination address.

Parameters

sock	Socket file descriptor.
buf	Data to send.
len	Number of bytes to send.
flags	MSG_* flags.
dest_addr	Destination address.
addrlen	Size of `dest_addr` in bytes.

Returns: Number of bytes sent on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/sendto.html

◆ sethostent()

void sethostent ( int stayopen )

Open the hosts database.

Parameters

stayopen Non-zero to keep the database connection open.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/sethostent.html

◆ setnetent()

void setnetent ( int stayopen )

Open the networks database.

Parameters

stayopen Non-zero to keep the database connection open.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/setnetent.html

◆ setprotoent()

void setprotoent ( int stayopen )

Open the protocols database.

Parameters

stayopen Non-zero to keep the database connection open.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/setprotoent.html

◆ setservent()

void setservent ( int stayopen )

Open the services database.

Parameters

stayopen Non-zero to keep the database connection open.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/setservent.html

◆ setsockopt()

int setsockopt	(	int	sock,
		int	level,
		int	optname,
		const void *	optval,
		socklen_t	optlen
	)

Set socket options.

Parameters

sock	Socket file descriptor.
level	Protocol level (SOL_SOCKET, IPPROTO_TCP, etc.).
optname	Option name.
optval	Pointer to the new option value.
optlen	Size of `optval` in bytes.

Returns: 0 on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/setsockopt.html

◆ shutdown()

int shutdown	(	int	sock,
		int	how
	)

Shut down part or all of a full-duplex connection.

Parameters

sock	Socket file descriptor.
how	SHUT_RD, SHUT_WR, or SHUT_RDWR.

Returns: 0 on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/shutdown.html

◆ sockatmark()

int sockatmark ( int s )

Determine whether a socket is at the out-of-band mark.

Parameters

s	Socket file descriptor.

Returns: 1 if at the mark, 0 if not, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/sockatmark.html

◆ socket()

int socket	(	int	family,
		int	type,
		int	proto
	)

Create a new socket.

Parameters

family	Protocol family (AF_INET, AF_INET6, AF_UNIX, etc.).
type	Socket type (SOCK_STREAM, SOCK_DGRAM, SOCK_RAW, etc.).
proto	Protocol number (IPPROTO_TCP, IPPROTO_UDP, 0 for default).

Returns: New socket file descriptor on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/socket.html

◆ socketpair()

int socketpair	(	int	family,
		int	type,
		int	proto,
		int	sv[2]
	)

Create a pair of connected sockets.

Parameters

family	Protocol family (typically AF_UNIX).
type	Socket type.
proto	Protocol.
sv	Output: two-element array receiving the socket descriptors.

Returns: 0 on success, or -1 with errno set on failure.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/functions/socketpair.html

Files

Functions

Detailed Description

Function Documentation

◆ accept()

◆ bind()

◆ connect()

◆ endhostent()

◆ endnetent()

◆ endprotoent()

◆ endservent()

◆ freeaddrinfo()

◆ gai_strerror()

◆ getaddrinfo()

◆ gethostent()

◆ gethostname()

◆ getnameinfo()

◆ getnetbyaddr()

◆ getnetbyname()

◆ getnetent()

◆ getpeername()

◆ getprotobyname()

◆ getprotobynumber()

◆ getprotoent()

◆ getservbyname()

◆ getservbyport()

◆ getservent()

◆ getsockname()

◆ getsockopt()

◆ if_freenameindex()

◆ if_indextoname()

◆ if_nameindex()

◆ if_nametoindex()

◆ inet_addr()

◆ inet_ntoa()

◆ inet_ntop()

◆ inet_pton()

◆ listen()

◆ recv()

◆ recvfrom()

◆ recvmsg()

◆ send()

◆ sendmsg()

◆ sendto()

◆ sethostent()

◆ setnetent()

◆ setprotoent()

◆ setservent()

◆ setsockopt()

◆ shutdown()

◆ sockatmark()

◆ socket()

◆ socketpair()