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 (<netinet/in.h>)

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

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

Macros
#define	NI_MAXSERV 32
	Reasonable buffer size for getnameinfo() service names.

#define	EAI_BADFLAGS DNS_EAI_BADFLAGS
	Flags argument to getaddrinfo() contained an invalid value.

#define	EAI_NONAME DNS_EAI_NONAME
	The name does not resolve for the supplied parameters.

#define	EAI_AGAIN DNS_EAI_AGAIN
	Temporary failure in name resolution.

#define	EAI_FAIL DNS_EAI_FAIL
	Non-recoverable failure in name resolution.

#define	EAI_NODATA DNS_EAI_NODATA
	The requested name is valid but has no address data.

#define	EAI_MEMORY DNS_EAI_MEMORY
	Memory allocation failure.

#define	EAI_SYSTEM DNS_EAI_SYSTEM
	A system error occurred; errno is set.

#define	EAI_SERVICE DNS_EAI_SERVICE
	Requested service not available for the given socket type.

#define	EAI_SOCKTYPE DNS_EAI_SOCKTYPE
	Socket type not supported.

#define	EAI_FAMILY DNS_EAI_FAMILY
	Address family not supported.

#define	EAI_OVERFLOW DNS_EAI_OVERFLOW
	Output buffer overflow.

#define	addrinfo zsock_addrinfo
	Address info structure (alias for zsock_addrinfo).

#define	SHUT_RD ZSOCK_SHUT_RD
	Shut down the read half of the connection.

#define	SHUT_WR ZSOCK_SHUT_WR
	Shut down the write half of the connection.

#define	SHUT_RDWR ZSOCK_SHUT_RDWR
	Shut down both halves of the connection.

#define	MSG_PEEK ZSOCK_MSG_PEEK
	Peek at incoming data without removing it from the queue.

#define	MSG_TRUNC ZSOCK_MSG_TRUNC
	Return the real length of the datagram even if it was truncated.

#define	MSG_DONTWAIT ZSOCK_MSG_DONTWAIT
	Enable non-blocking operation for this call only.

#define	MSG_WAITALL ZSOCK_MSG_WAITALL
	Block until all requested data has been received.

Typedefs
typedef uint32_t	in_addr_t
	Unsigned 32-bit IPv4 address (alias for in_addr_t).

typedef uint16_t	in_port_t
	Unsigned 16-bit Internet port number.

typedef uint32_t	in_addr_t
	Unsigned 32-bit IPv4 address.

typedef uint32_t	socklen_t
	Type for socket address length values.

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 (legacy, no-op on most systems).

void	endnetent (void)
	Close the networks database (legacy, no-op on most systems).

void	endprotoent (void)
	Close the protocols database (legacy).

void	endservent (void)
	Close the services database (legacy).

void	freeaddrinfo (struct zsock_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 zsock_addrinfo hints, struct zsock_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 (legacy, sequential).

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 (legacy).

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

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

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

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

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

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

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

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

void	sethostent (int stayopen)
	Open the hosts database (legacy).

void	setnetent (int stayopen)
	Open the networks database (legacy).

void	setprotoent (int stayopen)
	Open the protocols database (legacy).

void	setservent (int stayopen)
	Open the services database (legacy).

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.

Detailed Description

POSIX Networking option group.

Macro Definition Documentation

◆ addrinfo

#define addrinfo zsock_addrinfo

Address info structure (alias for zsock_addrinfo).

Definition at line 90 of file netdb.h.

◆ EAI_AGAIN

#define EAI_AGAIN DNS_EAI_AGAIN

Temporary failure in name resolution.

Definition at line 35 of file netdb.h.

◆ EAI_BADFLAGS

#define EAI_BADFLAGS DNS_EAI_BADFLAGS

Flags argument to getaddrinfo() contained an invalid value.

Definition at line 31 of file netdb.h.

◆ EAI_FAIL

#define EAI_FAIL DNS_EAI_FAIL

Non-recoverable failure in name resolution.

Definition at line 37 of file netdb.h.

◆ EAI_FAMILY

#define EAI_FAMILY DNS_EAI_FAMILY

Address family not supported.

Definition at line 49 of file netdb.h.

◆ EAI_MEMORY

#define EAI_MEMORY DNS_EAI_MEMORY

Memory allocation failure.

Definition at line 41 of file netdb.h.

◆ EAI_NODATA

#define EAI_NODATA DNS_EAI_NODATA

The requested name is valid but has no address data.

Definition at line 39 of file netdb.h.

◆ EAI_NONAME

#define EAI_NONAME DNS_EAI_NONAME

The name does not resolve for the supplied parameters.

Definition at line 33 of file netdb.h.

◆ EAI_OVERFLOW

#define EAI_OVERFLOW DNS_EAI_OVERFLOW

Output buffer overflow.

Definition at line 51 of file netdb.h.

◆ EAI_SERVICE

#define EAI_SERVICE DNS_EAI_SERVICE

Requested service not available for the given socket type.

Definition at line 45 of file netdb.h.

◆ EAI_SOCKTYPE

#define EAI_SOCKTYPE DNS_EAI_SOCKTYPE

Socket type not supported.

Definition at line 47 of file netdb.h.

◆ EAI_SYSTEM

#define EAI_SYSTEM DNS_EAI_SYSTEM

A system error occurred; errno is set.

Definition at line 43 of file netdb.h.

◆ MSG_DONTWAIT

#define MSG_DONTWAIT ZSOCK_MSG_DONTWAIT

Enable non-blocking operation for this call only.

Definition at line 38 of file socket.h.

◆ MSG_PEEK

#define MSG_PEEK ZSOCK_MSG_PEEK

Peek at incoming data without removing it from the queue.

Definition at line 34 of file socket.h.

◆ MSG_TRUNC

#define MSG_TRUNC ZSOCK_MSG_TRUNC

Return the real length of the datagram even if it was truncated.

Definition at line 36 of file socket.h.

◆ MSG_WAITALL

#define MSG_WAITALL ZSOCK_MSG_WAITALL

Block until all requested data has been received.

Definition at line 40 of file socket.h.

◆ NI_MAXSERV

#define NI_MAXSERV 32

Reasonable buffer size for getnameinfo() service names.

Definition at line 27 of file netdb.h.

◆ SHUT_RD

#define SHUT_RD ZSOCK_SHUT_RD

Shut down the read half of the connection.

Definition at line 27 of file socket.h.

◆ SHUT_RDWR

#define SHUT_RDWR ZSOCK_SHUT_RDWR

Shut down both halves of the connection.

Definition at line 31 of file socket.h.

◆ SHUT_WR

#define SHUT_WR ZSOCK_SHUT_WR

Shut down the write half of the connection.

Definition at line 29 of file socket.h.

Typedef Documentation

◆ in_addr_t [1/2]

typedef uint32_t in_addr_t

Unsigned 32-bit IPv4 address (alias for in_addr_t).

Definition at line 32 of file inet.h.

◆ in_addr_t [2/2]

typedef uint32_t in_addr_t

Unsigned 32-bit IPv4 address.

Definition at line 35 of file in.h.

◆ in_port_t

typedef uint16_t in_port_t

Unsigned 16-bit Internet port number.

Definition at line 32 of file in.h.

◆ socklen_t

typedef uint32_t socklen_t

Type for socket address length values.

Definition at line 48 of file socket.h.

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 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 (legacy, no-op on most systems).

◆ endnetent()

void endnetent ( void )

Close the networks database (legacy, no-op on most systems).

◆ endprotoent()

void endprotoent ( void )

Close the protocols database (legacy).

◆ endservent()

void endservent ( void )

Close the services database (legacy).

◆ freeaddrinfo()

void freeaddrinfo ( struct zsock_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 zsock_addrinfo *	hints,
		struct zsock_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 (legacy, sequential).

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

◆ 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 (legacy).

Parameters

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

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

◆ getnetbyname()

struct netent * getnetbyname ( const char * name )

Look up a network by name (legacy).

Parameters

name	Network name.

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

◆ getnetent()

struct netent * getnetent ( void )

Get the next entry from the networks database (legacy, sequential).

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

◆ 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 (legacy).

Parameters

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

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

◆ getprotobynumber()

struct protoent * getprotobynumber ( int proto )

Look up a protocol by number (legacy).

Parameters

proto Protocol number.

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

◆ getprotoent()

struct protoent * getprotoent ( void )

Get the next entry from the protocols database (legacy, sequential).

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

◆ getservbyname()

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

Look up a service by name and protocol (legacy).

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.

◆ getservbyport()

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

Look up a service by port number and protocol (legacy).

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.

◆ getservent()

struct servent * getservent ( void )

Get the next entry from the services database (legacy, sequential).

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

◆ 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.

◆ 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.

◆ 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 INADDR_NONE 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, -1 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_DONTWAIT, etc.).

Returns: Number of bytes received, 0 on connection closed, or -1 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 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 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_DONTWAIT, MSG_NOSIGNAL, etc.).

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

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

◆ sethostent()

void sethostent ( int stayopen )

Open the hosts database (legacy).

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 (legacy).

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 (legacy).

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 (legacy).

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 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 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

Macros

Typedefs

Functions

Detailed Description

Macro Definition Documentation

◆ addrinfo

◆ EAI_AGAIN

◆ EAI_BADFLAGS

◆ EAI_FAIL

◆ EAI_FAMILY

◆ EAI_MEMORY

◆ EAI_NODATA

◆ EAI_NONAME

◆ EAI_OVERFLOW

◆ EAI_SERVICE

◆ EAI_SOCKTYPE

◆ EAI_SYSTEM

◆ MSG_DONTWAIT

◆ MSG_PEEK

◆ MSG_TRUNC

◆ MSG_WAITALL

◆ NI_MAXSERV

◆ SHUT_RD

◆ SHUT_RDWR

◆ SHUT_WR

Typedef Documentation

◆ in_addr_t [1/2]

◆ in_addr_t [2/2]

◆ in_port_t

◆ socklen_t

Function Documentation

◆ accept()

◆ bind()

◆ connect()

◆ endhostent()

◆ endnetent()

◆ endprotoent()

◆ endservent()

◆ freeaddrinfo()

◆ gai_strerror()

◆ getaddrinfo()

◆ gethostent()

◆ 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()