Classes
struct	const_list_iterator
	A forward iterator for linked lists. More...

class	handle
	An RAII handle type which owns an opaque resource of a specified type, and calls a designated function to close the resource upon destruction. More...

struct	ipv4_address
	Wraps `struct sockaddr_in`, adding constructors for convenient initialization. More...

struct	ipv6_address
	Wraps `struct sockaddr_in6`, adding constructors for convenient initialization. More...

struct	memory_region
	A structure holding details about a memory-mapped file or device. More...

struct	unix_domain_address
	Wraps `struct sockaddr_in`, adding constructors for convenient initialization. More...

Typedefs
typedef w::handle< int, -1, ::close >	fd
	An RAII util::handle type for POSIX file descriptors. More...

Functions
template<typename T >
T	throw_if_eq (T value, T x, const char *message)
	Throw a std::system_error with `errno` if `value` `==` `x`, otherwise return `value`. More...

template<typename T >
T	throw_if_lt (T value, T x, const char *message)
	Throw a std::system_error with `errno` if `value` `<` `x`, otherwise return `value`. More...

template<typename T >
T	throw_if_ne (T value, T x, const char *message)
	Throw a std::system_error with `errno` if `value` `!=` `x`, otherwise return `value`. More...

template<typename T >
T	throw_if_nz (T value, const char *message)
	Throw a std::system_error with `errno` if `value` `!= 0`, otherwise return `value`. More...

template<typename T >
T	throw_if_z (T value, const char *message)
	Throw a std::system_error with `errno` if `value` `== 0`, otherwise return `value`. More...

w::fd	epoll_create (int size=sizeof(nullptr))
	Creates an epoll instance. More...

void	epoll_ctl (int epfd, int op, int fd, struct epoll_event *event=nullptr)
	Manipulates an epoll instance. More...

void	epoll_ctl (int epfd, int op, int fd, std::uint32_t events, void *user_data=nullptr)
	Manipulates an epoll instance. More...

void	epoll_ctl (int epfd, int op, int fd, std::uint32_t events, int user_data)
	Manipulates an epoll instance. More...

void	epoll_ctl (int epfd, int op, int fd, std::uint32_t events, std::uint32_t user_data)
	Manipulates an epoll instance. More...

void	epoll_ctl (int epfd, int op, int fd, std::uint32_t events, std::uint64_t user_data)
	Manipulates an epoll instance. More...

unsigned	epoll_wait (int epfd, struct epoll_event *events, int maxevents, std::chrono::milliseconds timeout=std::chrono::milliseconds(-1))
	Waits for events to occur on an epoll instance. More...

w::fd	eventfd (unsigned initval=0, int flags=0)
	Creates an event file descriptor. More...

std::uint64_t	eventfd_read (int evfd)
	Reads the current counter value of an event file descriptor; see the man page of `eventfd()` for a description of the counter and blocking semantics. More...

void	eventfd_write (int evfd, std::uint64_t value)
	Modifies the counter value of an event file descriptor; see the man page of `eventfd()` for a description of the counter semantics. More...

w::fd	timerfd_create (int clockid, int flags=0)
	Creates a timer file descriptor. More...

void	timerfd_settime (int fd, int flags, const struct itimerspec new_value, struct itimerspec old_value)
	Sets the timeout and repetition interval of a timer file descriptor. More...

std::pair< std::chrono::nanoseconds, std::chrono::nanoseconds >	timerfd_settime (int fd, int flags, std::chrono::nanoseconds interval, std::chrono::nanoseconds initial)
	Sets the timeout and repetition interval of a timer file descriptor. More...

int	fcntl (int fd, int cmd)
	Controls a file descriptor. More...

template<typename Argument >
int	fcntl (int fd, int cmd, const Argument &arg)
	Controls a file descriptor. More...

int	ioctl (int fd, unsigned long request, void *arg)
	Controls a device. More...

int	ioctl (int fd, unsigned long request, const void *arg)
	Controls a device. More...

template<typename Argument >
int	ioctl (int fd, unsigned long request, Argument &arg)
	Controls a device. More...

template<typename Argument >
int	ioctl (int fd, unsigned long request, const Argument &arg)
	Controls a device. More...

template<typename Argument >
Argument	ioctl (int fd, unsigned long request)
	Controls a device. More...

std::size_t	lseek (int fd, off_t offset, int whence)
	Sets the position of a file pointer for a file descriptor. More...

w::fd	open (const char *pathname, int flags)
	Opens and possibly creates a file. More...

w::fd	open (const char *pathname, int flags, mode_t mode)
	Opens and possibly creates a file. More...

std::pair< w::fd, w::fd >	pipe ()
	Creates a pipe. More...

std::size_t	read (int fd, void *buf, std::size_t count)
	Reads data from a file descriptor. More...

std::size_t	readv (int fd, const struct iovec *iov, int iovcnt)
	Reads data from a file descriptor. More...

std::size_t	write (int fd, const void *buf, std::size_t count)
	Writes data to a file descriptor. More...

std::size_t	writev (int fd, const struct iovec *iov, int iovcnt)
	Writes data to a file descriptor. More...

w::fd	accept (int sockfd, struct sockaddr addr, socklen_t addrlen)
	Accepts a connection on a socket. More...

template<typename Address >
w::fd	accept (int sockfd, Address &addr)
	Accepts a connection on a socket. More...

void	bind (int sockfd, const struct sockaddr *addr, socklen_t addrlen)
	Binds a socket to an address. More...

template<typename Address >
void	bind (int sockfd, const Address &addr)
	Binds a socket. More...

void	connect (int sockfd, const struct sockaddr *addr, socklen_t addrlen)
	Connects a socket. More...

template<typename Address >
void	connect (int sockfd, const Address &addr)
	Connects a socket. More...

w::handle< struct ifaddrs *, nullptr, ::freeifaddrs >	getifaddrs ()
	Gets a pointer to the head of a linked list of the system's network interfaces. More...

int	getsockopt (int sockfd, int level, int optname, void optval=nullptr, socklen_t optlen=nullptr)
	Gets an option on a socket. More...

template<typename Value >
Value	getsockopt (int sockfd, int level, int optname)
	Gets an option on a socket. More...

unsigned	if_nametoindex (const char *ifname)
	Returns the index of the specified network interface. More...

char *	inet_ntop (int af, const void src, char dst, socklen_t size)
	Converts an IPv4 or IPv6 address to a string. More...

void *	inet_pton (int af, const char src, void dst)
	Converts an IPv4 or IPv6 address from a string to a binary value. More...

template<typename Address >
Address &	inet_pton (int af, const char *src, Address &dst)
	Converts an IPv4 or IPv6 address from a string to a binary value. More...

void	listen (int sockfd, int backlog)
	Puts a socket in a listening state. More...

std::size_t	recv (int sockfd, void *buf, std::size_t len, int flags=0)
	Receives a message from a socket. More...

std::size_t	recvmsg (int sockfd, struct msghdr *msg, int flags=0)
	Receives a message from a socket. More...

std::size_t	recvfrom (int sockfd, void buf, std::size_t len, int flags, struct sockaddr src_addr=nullptr, socklen_t *addrlen=nullptr)
	Receives a message from a socket. More...

template<typename Address >
std::size_t	recvfrom (int sockfd, void *buf, std::size_t len, int flags, Address &src_addr)
	Receives a message from a socket. More...

std::size_t	send (int sockfd, const void *buf, std::size_t len, int flags=0)
	Sends a message on a socket. More...

std::size_t	sendmsg (int sockfd, const struct msghdr *msg, int flags=0)
	Sends a message on a socket. More...

std::size_t	sendto (int sockfd, const void buf, std::size_t len, int flags, const struct sockaddr dest_addr, socklen_t addrlen)
	Sends a message on a socket. More...

template<typename Address >
std::size_t	sendto (int sockfd, const void *buf, std::size_t len, int flags, const Address &dest_addr)
	Sends a message on a socket. More...

int	setsockopt (int sockfd, int level, int optname, const void *optval=nullptr, socklen_t optlen=0)
	Sets an option on a socket. More...

template<typename Value >
void	setsockopt (int sockfd, int level, int optname, const Value &optval)
	Sets an option on a socket. More...

void	shutdown (int sockfd, int how)
	Shuts down part of a full-duplex connection. More...

w::fd	socket (int domain, int type, int protocol=0)
	Creates a socket. More...

Typedef Documentation

◆ fd

typedef w::handle<int, -1, ::close> w::fd

An RAII util::handle type for POSIX file descriptors.

Function Documentation

◆ accept() [1/2]

template<typename Address >

w::fd w::accept	(	int	sockfd,
		Address &	addr
	)

Accepts a connection on a socket.

Template Parameters

Address The type of addr.

Parameters

sockfd	The socket on which to accept a connection.
addr	A reference to the address of the remote endpoint.

Exceptions

std::system_error	An error occurred.
std::runtime_error	The structure referenced by `addr` is not the correct size to hold the remote address.

◆ accept() [2/2]

w::fd w::accept	(	int	sockfd,
		struct sockaddr *	addr,
		socklen_t *	addrlen
	)

Accepts a connection on a socket.

Parameters

sockfd	The socket on which to accept a connection.
addr	A pointer to the address of the remote endpoint.
addrlen	A pointer to the size of the structure pointed to by `addr`, in bytes. On return, the value holds the actual size of the source address. This might be larger than the input value, in which case the address was truncated.

Returns: The socket file descriptor of the new connection.

Exceptions

std::system_error An error occurred.

◆ bind() [1/2]

template<typename Address >

void w::bind	(	int	sockfd,
		const Address &	addr
	)

Binds a socket.

Template Parameters

Address The type of addr.

Parameters

sockfd	The socket to bind.
addr	A reference to the address to bind to.

Exceptions

std::system_error An error occurred.

◆ bind() [2/2]

void w::bind	(	int	sockfd,
		const struct sockaddr *	addr,
		socklen_t	addrlen
	)

Binds a socket to an address.

Parameters

sockfd	The socket to bind.
addr	A pointer to the address to bind to.
addrlen	The size of the structure pointed to by `addr`, in bytes.

Exceptions

std::system_error An error occurred.

◆ connect() [1/2]

template<typename Address >

void w::connect	(	int	sockfd,
		const Address &	addr
	)

Connects a socket.

Template Parameters

Address The type of addr.

Parameters

sockfd	The socket to connect.
addr	A reference to the address to connect to.

Exceptions

std::system_error An error occurred.

◆ connect() [2/2]

void w::connect	(	int	sockfd,
		const struct sockaddr *	addr,
		socklen_t	addrlen
	)

Connects a socket.

Parameters

sockfd	The socket to connect.
addr	A pointer to the address to connect to.
addrlen	The size of the structure pointed to by `addr`, in bytes.

Exceptions

std::system_error An error occurred.

◆ epoll_create()

w::fd w::epoll_create ( int size = sizeof(nullptr) )

Creates an epoll instance.

Parameters

size	This value is ignored, but must be nonzero (see the man page).

Returns: The file descriptor for the epoll instance.

Exceptions

std::system_error An error occurred.

◆ epoll_ctl() [1/5]

void w::epoll_ctl	(	int	epfd,
		int	op,
		int	fd,
		std::uint32_t	events,
		int	user_data
	)

Manipulates an epoll instance.

Parameters

epfd	The epoll instance file descriptor.
op	The operation to perform.
fd	The file descriptor to add, modify or remove from the poll instance.
events	A bitwise combination of events of interest.
user_data	An opaque user data value.

Exceptions

std::system_error An error occurred.

◆ epoll_ctl() [2/5]

void w::epoll_ctl	(	int	epfd,
		int	op,
		int	fd,
		std::uint32_t	events,
		std::uint32_t	user_data
	)

Manipulates an epoll instance.

Parameters

epfd	The epoll instance file descriptor.
op	The operation to perform.
fd	The file descriptor to add, modify or remove from the poll instance.
events	A bitwise combination of events of interest.
user_data	An opaque user data value.

Exceptions

std::system_error An error occurred.

◆ epoll_ctl() [3/5]

void w::epoll_ctl	(	int	epfd,
		int	op,
		int	fd,
		std::uint32_t	events,
		std::uint64_t	user_data
	)

Manipulates an epoll instance.

Parameters

epfd	The epoll instance file descriptor.
op	The operation to perform.
fd	The file descriptor to add, modify or remove from the poll instance.
events	A bitwise combination of events of interest.
user_data	An opaque user data value.

Exceptions

std::system_error An error occurred.

◆ epoll_ctl() [4/5]

void w::epoll_ctl	(	int	epfd,
		int	op,
		int	fd,
		std::uint32_t	events,
		void *	user_data = `nullptr`
	)

Manipulates an epoll instance.

Parameters

epfd	The epoll instance file descriptor.
op	The operation to perform.
fd	The file descriptor to add, modify or remove from the poll instance.
events	A bitwise combination of events of interest.
user_data	An opaque user data value.

Exceptions

std::system_error An error occurred.

◆ epoll_ctl() [5/5]

void w::epoll_ctl	(	int	epfd,
		int	op,
		int	fd,
		struct epoll_event *	event = `nullptr`
	)

Manipulates an epoll instance.

Parameters

epfd	The epoll instance file descriptor.
op	The operation to perform.
fd	The file descriptor to add, modify or remove from the poll instance.
event	A pointer to a structure specifying the events of interest.

Exceptions

std::system_error An error occurred.

◆ epoll_wait()

unsigned w::epoll_wait	(	int	epfd,
		struct epoll_event *	events,
		int	maxevents,
		std::chrono::milliseconds	timeout = `std::chrono::milliseconds(-1)`
	)

Waits for events to occur on an epoll instance.

Parameters

epfd	The epoll instance file descriptor.
events	A pointer to an array of structures to receive information about events.
maxevents	The number of elements in the `events` array.
timeout	The number of milliseconds

Returns: The number of events that occurred, which may be zero.

Exceptions

std::invalid_argument	`timeout` is out of range.
std::system_error	An error occurred.

◆ eventfd()

w::fd w::eventfd	(	unsigned	initval = `0`,
		int	flags = `0`
	)

Creates an event file descriptor.

Parameters

initval	The initial value of the eventfd counter.
flags	Flags that affect the created event file descriptor.

◆ eventfd_read()

std::uint64_t w::eventfd_read ( int evfd )

Reads the current counter value of an event file descriptor; see the man page of eventfd() for a description of the counter and blocking semantics.

Parameters

evfd	The event file descriptor.

Returns: The event counter value.

Exceptions

std::system_error An error occurred.

◆ eventfd_write()

void w::eventfd_write	(	int	evfd,
		std::uint64_t	value
	)

Modifies the counter value of an event file descriptor; see the man page of eventfd() for a description of the counter semantics.

Parameters

evfd	The event file descriptor.
value	The event counter value.

Exceptions

std::system_error An error occurred.

◆ fcntl() [1/2]

int w::fcntl	(	int	fd,
		int	cmd
	)

Controls a file descriptor.

Parameters

fd	The file descriptor to control.
cmd	The control command code.

Returns: A result code from the command.

Exceptions

std:system_error An error occurred.

◆ fcntl() [2/2]

template<typename Argument >

int w::fcntl	(	int	fd,
		int	cmd,
		const Argument &	arg
	)

Controls a file descriptor.

Template Parameters

Argument The type of the command-specific argument.

Parameters

fd	The file descriptor to control.
cmd	The control command code.
arg	A reference to a command-specific input argument.

Returns: A result code from the command.

Exceptions

std:system_error An error occurred.

◆ getifaddrs()

w::handle< struct ifaddrs *, nullptr,::freeifaddrs > w::getifaddrs ( )

Gets a pointer to the head of a linked list of the system's network interfaces.

Returns: A pointer to the head of a linked list of the system's network interfaces.

Exceptions

std::system_error An error occurred.

◆ getsockopt() [1/2]

template<typename Value >

Value w::getsockopt	(	int	sockfd,
		int	level,
		int	optname
	)

Gets an option on a socket.

Parameters

sockfd	The socket on which to get the option.
level	The option level.
optname	The option to get.

Returns: The value returned for the option.

Exceptions

std::system_error	An error occurred.
std::runtime_error	`Value` has the wrong size for this option.

◆ getsockopt() [2/2]

int w::getsockopt	(	int	sockfd,
		int	level,
		int	optname,
		void *	optval = `nullptr`,
		socklen_t *	optlen = `nullptr`
	)

Gets an option on a socket.

Parameters

sockfd	The socket on which to get the option.
level	The option level.
optname	The option to get.
optval	A pointer to the value to be filled in.
optlen	A pointer to the size of the value pointed to by `optval`. On return, the value holds the actual size of the value. This might be larger than the input value, in which case the value was truncated.

Returns: The return value of the option (which cannot be -1).

Exceptions

std::system_error An error occurred.

◆ if_nametoindex()

unsigned w::if_nametoindex ( const char * ifname )

Returns the index of the specified network interface.

Parameters

ifname The name of the network interface.

Returns: The nonzero index of the network interface.

Exceptions

std::system_error An error occurred.

◆ inet_ntop()

char * w::inet_ntop	(	int	af,
		const void *	src,
		char *	dst,
		socklen_t	size
	)

Converts an IPv4 or IPv6 address to a string.

Parameters

af	The address family.
src	A pointer to the address.
dst	A pointer to a character buffer to be filled.
size	The size of the buffer pointed to by `dst`, in bytes.

Returns: dst.

Exceptions

std::system_error An error occurred.

◆ inet_pton() [1/2]

template<typename Address >

Address & w::inet_pton	(	int	af,
		const char *	src,
		Address &	dst
	)

Converts an IPv4 or IPv6 address from a string to a binary value.

Parameters

af	The address family.
src	A pointer to the address string.
dst	A reference to a socket address structure to be filled.

Returns: dst.

Exceptions

std::system_error An error occurred.

◆ inet_pton() [2/2]

void * w::inet_pton	(	int	af,
		const char *	src,
		void *	dst
	)

Converts an IPv4 or IPv6 address from a string to a binary value.

Parameters

af	The address family.
src	A pointer to the address string.
dst	A pointer to a socket address structure to be filled.

Returns: dst.

Exceptions

std::system_error An error occurred.

◆ ioctl() [1/5]

template<typename Argument >

Argument w::ioctl	(	int	fd,
		unsigned long	request
	)

Controls a device.

Template Parameters

Argument The type of the request's output value.

Parameters

fd	The file descriptor of the device to control.
request	The control request code.

Returns: The output value.

Exceptions

std:system_error An error occurred.

◆ ioctl() [2/5]

template<typename Argument >

int w::ioctl	(	int	fd,
		unsigned long	request,
		Argument &	arg
	)

Controls a device.

Template Parameters

Argument The type of arg.

Parameters

fd	The file descriptor of the device to control.
request	The control request code.
arg	A pointer to a request-specific input argument.

Returns: A nonnegative result code from the control request.

Exceptions

std:system_error An error occurred.

◆ ioctl() [3/5]

template<typename Argument >

int w::ioctl	(	int	fd,
		unsigned long	request,
		const Argument &	arg
	)

Controls a device.

Note that the library cannot guarantee the underlying ioctl call will not modify its argument. Therefore, when using this overload, it is the caller's responsibility to somehow ensure the ioctl does not modify its argument, or the behavior is undefined.

Template Parameters

Argument The type of arg.

Parameters

fd	The file descriptor of the device to control.
request	The control request code.
arg	A pointer to a request-specific input argument.

Returns: A nonnegative result code from the control request.

Exceptions

std:system_error An error occurred.

◆ ioctl() [4/5]

int w::ioctl	(	int	fd,
		unsigned long	request,
		const void *	arg
	)

Controls a device.

Note that the library cannot guarantee the underlying ioctl call will not modify its argument. Therefore, when using this overload, it is the caller's responsibility to somehow ensure the ioctl does not modify its argument, or the behavior is undefined.

Parameters

fd	The file descriptor of the device to control.
request	The control request code.
arg	A pointer to a request-specific input argument.

Returns: A nonnegative result code from the control request.

Exceptions

std:system_error An error occurred.

◆ ioctl() [5/5]

int w::ioctl	(	int	fd,
		unsigned long	request,
		void *	arg
	)

Controls a device.

Parameters

fd	The file descriptor of the device to control.
request	The control request code.
arg	A pointer to a request-specific output argument.

Returns: A nonnegative result code from the control request.

Exceptions

std:system_error An error occurred.

◆ listen()

void w::listen	(	int	sockfd,
		int	backlog
	)

Puts a socket in a listening state.

Parameters

sockfd	The socket to listen on.
backlog	The maximum number of pending connections to allow.

Exceptions

std::system_error An error occurred.

◆ lseek()

std::size_t w::lseek	(	int	fd,
		off_t	offset,
		int	whence
	)

Sets the position of a file pointer for a file descriptor.

Parameters

fd	The file descriptor to seek in.
offset	The offset to seek to.
whence	`SEEK_SET`, `SEEK_CUR` or `SEEK_END`.

Returns: The new offset relative to the beginning of the file.

Exceptions

std::system_error An error occurred.

◆ open() [1/2]

w::fd w::open	(	const char *	pathname,
		int	flags
	)

Opens and possibly creates a file.

Parameters

pathname	The path of the file to open and/or create.
flags	A bitwise combination of flags.

Returns: A file descriptor for the opened file.

Exceptions

std:system_error An error occurred.

◆ open() [2/2]

w::fd w::open	(	const char *	pathname,
		int	flags,
		mode_t	mode
	)

Opens and possibly creates a file.

Parameters

pathname	The path of the file to open and/or create.
flags	A bitwise combination of flags.
mode	The access mode for the file.

Returns: A file descriptor for the opened file.

Exceptions

std:system_error An error occurred.

◆ pipe()

std::pair< w::fd, w::fd > w::pipe ( )

Creates a pipe.

Returns: A pair of file descriptors for the read and write ends of the pipe, respectively.

Exceptions

std:system_error An error occurred.

◆ read()

std::size_t w::read	(	int	fd,
		void *	buf,
		std::size_t	count
	)

Reads data from a file descriptor.

Parameters

fd	The file descriptor to read from.
buf	A pointer to an array where read data should be stored.
count	The maximum number of bytes to read.

Returns: The number of bytes actually read, which may be zero.

Exceptions

std::system_error An error occurred. This includes EAGAIN on non-blocking files.

◆ readv()

std::size_t w::readv	(	int	fd,
		const struct iovec *	iov,
		int	iovcnt
	)

Reads data from a file descriptor.

Parameters

fd	The file descriptor to read from.
iov	A pointer to an array of `iovec` scatter-gather structures.
iovcnt	The number of structures in the array pointed to by `iov`.

Returns: The number of bytes actually read, which may be zero.

Exceptions

std::system_error An error occurred. This includes EAGAIN on non-blocking files.

◆ recv()

std::size_t w::recv	(	int	sockfd,
		void *	buf,
		std::size_t	len,
		int	flags = `0`
	)

Receives a message from a socket.

Parameters

sockfd	The socket to receive from.
buf	A pointer to an array where received data should be stored.
len	The maximum number of bytes to receive.
flags	A bitwise combination of flags.

Returns: The number of bytes successfully received (which may be zero).

Exceptions

std::system_error An error occurred. This includes EAGAIN on non-blocking sockets.

◆ recvfrom() [1/2]

template<typename Address >

std::size_t w::recvfrom	(	int	sockfd,
		void *	buf,
		std::size_t	len,
		int	flags,
		Address &	src_addr
	)

Receives a message from a socket.

Template Parameters

Address The type of src_addr.

Parameters

sockfd	The socket to receive from.
buf	A pointer to an array where received data should be stored.
len	The maximum number of bytes to receive.
flags	A bitwise combination of flags.
src_addr	A reference to the source address.

Returns: The number of bytes successfully received (which may be zero).

Exceptions

std::system_error	An error occurred. This includes `EAGAIN` on non-blocking sockets.
std::runtime_error	The structure referenced by `src_addr` is not the correct size to hold the source address.

◆ recvfrom() [2/2]

std::size_t w::recvfrom	(	int	sockfd,
		void *	buf,
		std::size_t	len,
		int	flags,
		struct sockaddr *	src_addr = `nullptr`,
		socklen_t *	addrlen = `nullptr`
	)

Receives a message from a socket.

Parameters

sockfd	The socket to receive from.
buf	A pointer to an array where received data should be stored.
len	The maximum number of bytes to receive.
flags	A bitwise combination of flags.
src_addr	A pointer to the source address.
addrlen	A pointer to the size of the structure pointed to by `src_addr`, in bytes. On return, the value holds the actual size of the source address. This might be larger than the input value, in which case the address was truncated.

Returns: The number of bytes successfully received (which may be zero).

Exceptions

std::system_error	An error occurred. This includes `EAGAIN` on non-blocking sockets.
std::runtime_error	The structure pointed to by `src_addr` is too small to hold the source address.

◆ recvmsg()

std::size_t w::recvmsg	(	int	sockfd,
		struct msghdr *	msg,
		int	flags = `0`
	)

Receives a message from a socket.

Parameters

sockfd	The socket to receive from.
msg	A pointer to a message structure to be filled in.
flags	A bitwise combination of flags.

Returns: The number of bytes successfully received (which may be zero).

Exceptions

std::system_error An error occurred. This includes EAGAIN on non-blocking sockets.

◆ send()

std::size_t w::send	(	int	sockfd,
		const void *	buf,
		std::size_t	len,
		int	flags = `0`
	)

Sends a message on a socket.

Parameters

sockfd	The socket to send from.
buf	A pointer to the data to send.
len	The maximum number of bytes to send.
flags	A bitwise combination of flags.

Returns: The number of bytes successfully accepted for transmission (which may be zero).

Exceptions

std::system_error An error occurred. This includes EAGAIN on non-blocking sockets.

◆ sendmsg()

std::size_t w::sendmsg	(	int	sockfd,
		const struct msghdr *	msg,
		int	flags = `0`
	)

Sends a message on a socket.

Parameters

sockfd	The socket to send from.
msg	A pointer to a message structure describing the message to send.
flags	A bitwise combination of flags.

Returns: The number of bytes successfully accepted for transmission (which may be zero).

Exceptions

std::system_error An error occurred. This includes EAGAIN on non-blocking sockets.

◆ sendto() [1/2]

template<typename Address >

std::size_t w::sendto	(	int	sockfd,
		const void *	buf,
		std::size_t	len,
		int	flags,
		const Address &	dest_addr
	)

Sends a message on a socket.

Template Parameters

Address The type of dest_addr.

Parameters

sockfd	The socket to send from.
buf	A pointer to the data to send.
len	The number of bytes to send.
flags	A bitwise combination of flags.
dest_addr	A reference to the destination address.

Returns: The number of bytes successfully accepted for transmission (which may be zero).

Exceptions

std::system_error An error occurred. This includes EAGAIN on non-blocking sockets.

◆ sendto() [2/2]

std::size_t w::sendto	(	int	sockfd,
		const void *	buf,
		std::size_t	len,
		int	flags,
		const struct sockaddr *	dest_addr,
		socklen_t	addrlen
	)

Sends a message on a socket.

Parameters

sockfd	The socket to send from.
buf	A pointer to the data to send.
len	The maximum number of bytes to send.
flags	A bitwise combination of flags.
dest_addr	A pointer to the destination address.
addrlen	The size of the structure pointed to by `dest_addr`, in bytes.

Returns: The number of bytes successfully accepted for transmission (which may be zero).

Exceptions

std::system_error An error occurred. This includes EAGAIN on non-blocking sockets.

◆ setsockopt() [1/2]

template<typename Value >

void w::setsockopt	(	int	sockfd,
		int	level,
		int	optname,
		const Value &	optval
	)

Sets an option on a socket.

Template Parameters

Value The type of optval.

Parameters

sockfd	The socket on which to set the option.
level	The option level.
optname	The option to set.
optval	A reference to the value to set.

Exceptions

std::system_error An error occurred.

◆ setsockopt() [2/2]

int w::setsockopt	(	int	sockfd,
		int	level,
		int	optname,
		const void *	optval = `nullptr`,
		socklen_t	optlen = `0`
	)

Sets an option on a socket.

Parameters

sockfd	The socket on which to set the option.
level	The option level.
optname	The option to set.
optval	A pointer to the value to set.
optlen	The size of the value pointed to by `optval`, in bytes.

Returns: The return value of the option (which cannot be -1).

Exceptions

std::system_error An error occurred.

◆ shutdown()

void w::shutdown	(	int	sockfd,
		int	how
	)

Shuts down part of a full-duplex connection.

Parameters

sockfd	The socket to shut down.
how	A flag specifying what to shut down.

Exceptions

std::system_error An error occurred.

◆ socket()

w::fd w::socket	(	int	domain,
		int	type,
		int	protocol = `0`
	)

Creates a socket.

Parameters

domain	The communication domain.
type	The type of socket.
protocol	The protocol on which to communicate.

Returns: The created socket.

Exceptions

std::system_error An error occurred.

◆ throw_if_eq()

template<typename T >

T w::throw_if_eq	(	T	value,
		T	x,
		const char *	message
	)

Throw a std::system_error with errno if value == x, otherwise return value.

Template Parameters

T	The type of `value` and `x`.

Parameters

value	The value to check.
x	The value to test for.
message	The message to include in the exception.

Returns: value.

Exceptions

std::system_error value == x. The error code is set to errno.

◆ throw_if_lt()

template<typename T >

T w::throw_if_lt	(	T	value,
		T	x,
		const char *	message
	)

Throw a std::system_error with errno if value < x, otherwise return value.

Template Parameters

T	The type of `value` and `x`.

Parameters

value	The value to check.
x	The value to test for.
message	The message to include in the exception.

Returns: value.

Exceptions

std::system_error value < x. The error code is set to errno.

◆ throw_if_ne()

template<typename T >

T w::throw_if_ne	(	T	value,
		T	x,
		const char *	message
	)

Throw a std::system_error with errno if value != x, otherwise return value.

Template Parameters

T	The type of `value` and `x`.

Parameters

value	The value to check.
x	The value to test for.
message	The message to include in the exception.

Returns: value.

Exceptions

std::system_error value != x. The error code is set to errno.

◆ throw_if_nz()

template<typename T >

T w::throw_if_nz	(	T	value,
		const char *	message
	)

Throw a std::system_error with errno if value != 0, otherwise return value.

Template Parameters

T	The type of `value`.

Parameters

value	The value to check.
message	The message to include in the exception.

Returns: value.

Exceptions

std::system_error value != 0. The error code is set to errno.

◆ throw_if_z()

template<typename T >

T w::throw_if_z	(	T	value,
		const char *	message
	)

Throw a std::system_error with errno if value == 0, otherwise return value.

Template Parameters

T	The type of `value`.

Parameters

value	The value to check.
message	The message to include in the exception.

Returns: value.

Exceptions

std::system_error value == 0. The error code is set to errno.

◆ timerfd_create()

w::fd w::timerfd_create	(	int	clockid,
		int	flags = `0`
	)

Creates a timer file descriptor.

Parameters

clockid	The identifier of the clock on which the timer should be based.
flags	A bitwise combination of flags.

Returns: The file descriptor for the created timer.

Exceptions

std::system_error An error occurred.

◆ timerfd_settime() [1/2]

void w::timerfd_settime	(	int	fd,
		int	flags,
		const struct itimerspec *	new_value,
		struct itimerspec *	old_value
	)

Sets the timeout and repetition interval of a timer file descriptor.

Parameters

fd	The timer file descriptor to adjust.
flags	A bitwise combination of flags.
new_value	A pointer to a structure containing the repetition interval and initial expiration time.
old_value	A pointer to a structure to be filled in with the previous repetition interval and expiration time.

Exceptions

std::system_error An error occurred.

◆ timerfd_settime() [2/2]

std::pair< std::chrono::nanoseconds, std::chrono::nanoseconds > w::timerfd_settime	(	int	fd,
		int	flags,
		std::chrono::nanoseconds	interval,
		std::chrono::nanoseconds	initial
	)

Sets the timeout and repetition interval of a timer file descriptor.

Parameters

fd	The timer file descriptor to adjust.
flags	A bitwise combination of flags.
interval	The repetition interval.
initial	The initial expiration time.

Returns: A pair consisting of the previous repetition interval and initial expiration time, in that order.

Exceptions

std::system_error An error occurred.

◆ write()

std::size_t w::write	(	int	fd,
		const void *	buf,
		std::size_t	count
	)

Writes data to a file descriptor.

Parameters

fd	The file descriptor to write to.
buf	A pointer to an array of data to write.
count	The maximum number of bytes to write.

Returns: The number of bytes actually written, which may be zero.

Exceptions

std::system_error An error occurred. This includes EAGAIN on non-blocking files.

◆ writev()

std::size_t w::writev	(	int	fd,
		const struct iovec *	iov,
		int	iovcnt
	)

Writes data to a file descriptor.

Parameters

fd	The file descriptor to write to.
iov	A pointer to an array of `iovec` scatter-gather structures.
iovcnt	The number of structures in the array pointed to by `iov`.

Returns: The number of bytes actually written, which may be zero.

Exceptions

std::system_error An error occurred. This includes EAGAIN on non-blocking files.

Classes

Typedefs

Functions

Typedef Documentation

◆ fd

Function Documentation

◆ accept() [1/2]

◆ accept() [2/2]

◆ bind() [1/2]

◆ bind() [2/2]

◆ connect() [1/2]

◆ connect() [2/2]

◆ epoll_create()

◆ epoll_ctl() [1/5]

◆ epoll_ctl() [2/5]

◆ epoll_ctl() [3/5]

◆ epoll_ctl() [4/5]

◆ epoll_ctl() [5/5]

◆ epoll_wait()

◆ eventfd()

◆ eventfd_read()

◆ eventfd_write()

◆ fcntl() [1/2]

◆ fcntl() [2/2]

◆ getifaddrs()

◆ getsockopt() [1/2]

◆ getsockopt() [2/2]

◆ if_nametoindex()

◆ inet_ntop()

◆ inet_pton() [1/2]

◆ inet_pton() [2/2]

◆ ioctl() [1/5]

◆ ioctl() [2/5]

◆ ioctl() [3/5]

◆ ioctl() [4/5]

◆ ioctl() [5/5]

◆ listen()

◆ lseek()

◆ open() [1/2]

◆ open() [2/2]

◆ pipe()

◆ read()

◆ readv()

◆ recv()

◆ recvfrom() [1/2]

◆ recvfrom() [2/2]

◆ recvmsg()

◆ send()

◆ sendmsg()

◆ sendto() [1/2]

◆ sendto() [2/2]

◆ setsockopt() [1/2]

◆ setsockopt() [2/2]

◆ shutdown()

◆ socket()

◆ throw_if_eq()

◆ throw_if_lt()

◆ throw_if_ne()

◆ throw_if_nz()

◆ throw_if_z()

◆ timerfd_create()

◆ timerfd_settime() [1/2]

◆ timerfd_settime() [2/2]

◆ write()

◆ writev()