const (
IPv4len = 4
IPv6len = 16
)
IP address lengths (bytes).
var (
IPv4bcast = IPv4(255, 255, 255, 255) // broadcast
IPv4allsys = IPv4(224, 0, 0, 1) // all systems
IPv4allrouter = IPv4(224, 0, 0, 2) // all routers
IPv4zero = IPv4(0, 0, 0, 0) // all zeros
)
Well-known IPv4 addresses
var (
IPv6zero = IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
IPv6unspecified = IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
IPv6loopback = IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
IPv6interfacelocalallnodes = IP{0xff, 0x01, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01}
IPv6linklocalallnodes = IP{0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01}
IPv6linklocalallrouters = IP{0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x02}
)
Well-known IPv6 addresses
var (
ErrWriteToConnected = errors.New("use of WriteTo with pre-connected connection")
)
Various errors contained in OpError.
func InterfaceAddrs() ([]Addr, error)
InterfaceAddrs returns a list of the system's network interface addresses.
func Interfaces() ([]Interface, error)
Interfaces returns a list of the system's network interfaces.
func JoinHostPort(host, port string) string
JoinHostPort combines host and port into a network address of the form "host:port" or, if host contains a colon or a percent sign, "[host]:port".
func LookupAddr(addr string) (names []string, err error)
LookupAddr performs a reverse lookup for the given address, returning a list of names mapping to that address.
func LookupCNAME(name string) (cname string, err error)
LookupCNAME returns the canonical DNS host for the given name. Callers that do not care about the canonical name can call LookupHost or LookupIP directly; both take care of resolving the canonical name as part of the lookup.
func LookupHost(host string) (addrs []string, err error)
LookupHost looks up the given host using the local resolver. It returns an array of that host's addresses.
func LookupIP(host string) (ips []IP, err error)
LookupIP looks up host using the local resolver. It returns an array of that host's IPv4 and IPv6 addresses.
func LookupMX(name string) (mxs []*MX, err error)
LookupMX returns the DNS MX records for the given domain name sorted by preference.
func LookupNS(name string) (nss []*NS, err error)
LookupNS returns the DNS NS records for the given domain name.
func LookupPort(network, service string) (port int, err error)
LookupPort looks up the port for the given network and service.
func LookupSRV(service, proto, name string) (cname string, addrs []*SRV, err error)
LookupSRV tries to resolve an SRV query of the given service, protocol, and domain name. The proto is "tcp" or "udp". The returned records are sorted by priority and randomized by weight within a priority.
LookupSRV constructs the DNS name to look up following RFC 2782. That is, it looks up _service._proto.name. To accommodate services publishing SRV records under non-standard names, if both service and proto are empty strings, LookupSRV looks up name directly.
func LookupTXT(name string) (txts []string, err error)
LookupTXT returns the DNS TXT records for the given domain name.
func SplitHostPort(hostport string) (host, port string, err error)
SplitHostPort splits a network address of the form "host:port", "[host]:port" or "[ipv6-host%zone]:port" into host or ipv6-host%zone and port. A literal address or host name for IPv6 must be enclosed in square brackets, as in "[::1]:80", "[ipv6-host]:http" or "[ipv6-host%zone]:80".
type Addr interface {
Network() string // name of the network
String() string // string form of address
}
Addr represents a network end point address.
type AddrError struct {
Err string
Addr string
}
func (e *AddrError) Error() string
func (e *AddrError) Temporary() bool
func (e *AddrError) Timeout() bool
type Conn interface {
// Read reads data from the connection.
// Read can be made to time out and return a Error with Timeout() == true
// after a fixed time limit; see SetDeadline and SetReadDeadline.
Read(b []byte) (n int, err error)
// Write writes data to the connection.
// Write can be made to time out and return a Error with Timeout() == true
// after a fixed time limit; see SetDeadline and SetWriteDeadline.
Write(b []byte) (n int, err error)
// Close closes the connection.
// Any blocked Read or Write operations will be unblocked and return errors.
Close() error
// LocalAddr returns the local network address.
LocalAddr() Addr
// RemoteAddr returns the remote network address.
RemoteAddr() Addr
// SetDeadline sets the read and write deadlines associated
// with the connection. It is equivalent to calling both
// SetReadDeadline and SetWriteDeadline.
//
// A deadline is an absolute time after which I/O operations
// fail with a timeout (see type Error) instead of
// blocking. The deadline applies to all future I/O, not just
// the immediately following call to Read or Write.
//
// An idle timeout can be implemented by repeatedly extending
// the deadline after successful Read or Write calls.
//
// A zero value for t means I/O operations will not time out.
SetDeadline(t time.Time) error
// SetReadDeadline sets the deadline for future Read calls.
// A zero value for t means Read will not time out.
SetReadDeadline(t time.Time) error
// SetWriteDeadline sets the deadline for future Write calls.
// Even if write times out, it may return n > 0, indicating that
// some of the data was successfully written.
// A zero value for t means Write will not time out.
SetWriteDeadline(t time.Time) error
}
Conn is a generic stream-oriented network connection.
Multiple goroutines may invoke methods on a Conn simultaneously.
func Dial(network, address string) (Conn, error)
Dial connects to the address on the named network.
Known networks are "tcp", "tcp4" (IPv4-only), "tcp6" (IPv6-only), "udp", "udp4" (IPv4-only), "udp6" (IPv6-only), "ip", "ip4" (IPv4-only), "ip6" (IPv6-only), "unix", "unixgram" and "unixpacket".
For TCP and UDP networks, addresses have the form host:port. If host is a literal IPv6 address it must be enclosed in square brackets as in "[::1]:80" or "[ipv6-host%zone]:80". The functions JoinHostPort and SplitHostPort manipulate addresses in this form. If the host is empty, as in ":80", the local system is assumed.
Examples:
Dial("tcp", "12.34.56.78:80")
Dial("tcp", "google.com:http")
Dial("tcp", "[2001:db8::1]:http")
Dial("tcp", "[fe80::1%lo0]:80")
Dial("tcp", ":80")
For IP networks, the network must be "ip", "ip4" or "ip6" followed by a colon and a protocol number or name and the addr must be a literal IP address.
Examples:
Dial("ip4:1", "127.0.0.1")
Dial("ip6:ospf", "::1")
For Unix networks, the address must be a file system path.
func DialTimeout(network, address string, timeout time.Duration) (Conn, error)
DialTimeout acts like Dial but takes a timeout. The timeout includes name resolution, if required.
func FileConn(f *os.File) (c Conn, err error)
FileConn returns a copy of the network connection corresponding to the open file f. It is the caller's responsibility to close f when finished. Closing c does not affect f, and closing f does not affect c.
func Pipe() (Conn, Conn)
Pipe creates a synchronous, in-memory, full duplex network connection; both ends implement the Conn interface. Reads on one end are matched with writes on the other, copying data directly between the two; there is no internal buffering.
type DNSConfigError struct {
Err error
}
DNSConfigError represents an error reading the machine's DNS configuration. (No longer used; kept for compatibility.)
func (e *DNSConfigError) Error() string
func (e *DNSConfigError) Temporary() bool
func (e *DNSConfigError) Timeout() bool
type DNSError struct {
Err string // description of the error
Name string // name looked for
Server string // server used
IsTimeout bool // if true, timed out; not all timeouts set this
IsTemporary bool // if true, error is temporary; not all errors set this
}
DNSError represents a DNS lookup error.
func (e *DNSError) Error() string
func (e *DNSError) Temporary() bool
Temporary reports whether the DNS error is known to be temporary. This is not always known; a DNS lookup may fail due to a temporary error and return a DNSError for which Temporary returns false.
func (e *DNSError) Timeout() bool
Timeout reports whether the DNS lookup is known to have timed out. This is not always known; a DNS lookup may fail due to a timeout and return a DNSError for which Timeout returns false.
type Dialer struct {
// Timeout is the maximum amount of time a dial will wait for
// a connect to complete. If Deadline is also set, it may fail
// earlier.
//
// The default is no timeout.
//
// When dialing a name with multiple IP addresses, the timeout
// may be divided between them.
//
// With or without a timeout, the operating system may impose
// its own earlier timeout. For instance, TCP timeouts are
// often around 3 minutes.
Timeout time.Duration
// Deadline is the absolute point in time after which dials
// will fail. If Timeout is set, it may fail earlier.
// Zero means no deadline, or dependent on the operating system
// as with the Timeout option.
Deadline time.Time
// LocalAddr is the local address to use when dialing an
// address. The address must be of a compatible type for the
// network being dialed.
// If nil, a local address is automatically chosen.
LocalAddr Addr
// DualStack enables RFC 6555-compliant "Happy Eyeballs" dialing
// when the network is "tcp" and the destination is a host name
// with both IPv4 and IPv6 addresses. This allows a client to
// tolerate networks where one address family is silently broken.
DualStack bool
// FallbackDelay specifies the length of time to wait before
// spawning a fallback connection, when DualStack is enabled.
// If zero, a default delay of 300ms is used.
FallbackDelay time.Duration
// KeepAlive specifies the keep-alive period for an active
// network connection.
// If zero, keep-alives are not enabled. Network protocols
// that do not support keep-alives ignore this field.
KeepAlive time.Duration
// Cancel is an optional channel whose closure indicates that
// the dial should be canceled. Not all types of dials support
// cancelation.
Cancel <-chan struct{}
}
A Dialer contains options for connecting to an address.
The zero value for each field is equivalent to dialing without that option. Dialing with the zero value of Dialer is therefore equivalent to just calling the Dial function.
func (d *Dialer) Dial(network, address string) (Conn, error)
Dial connects to the address on the named network.
See func Dial for a description of the network and address parameters.
type Error interface {
error
Timeout() bool // Is the error a timeout?
Temporary() bool // Is the error temporary?
}
An Error represents a network error.
type Flags uint
const (
FlagUp Flags = 1 << iota // interface is up
FlagBroadcast // interface supports broadcast access capability
FlagLoopback // interface is a loopback interface
FlagPointToPoint // interface belongs to a point-to-point link
FlagMulticast // interface supports multicast access capability
)
func (f Flags) String() string
type HardwareAddr []byte
A HardwareAddr represents a physical hardware address.
func ParseMAC(s string) (hw HardwareAddr, err error)
ParseMAC parses s as an IEEE 802 MAC-48, EUI-48, EUI-64, or a 20-octet IP over InfiniBand link-layer address using one of the following formats:
01:23:45:67:89:ab 01:23:45:67:89:ab:cd:ef 01:23:45:67:89:ab:cd:ef:00:00:01:23:45:67:89:ab:cd:ef:00:00 01-23-45-67-89-ab 01-23-45-67-89-ab-cd-ef 01-23-45-67-89-ab-cd-ef-00-00-01-23-45-67-89-ab-cd-ef-00-00 0123.4567.89ab 0123.4567.89ab.cdef 0123.4567.89ab.cdef.0000.0123.4567.89ab.cdef.0000
func (a HardwareAddr) String() string
type IP []byte
An IP is a single IP address, a slice of bytes. Functions in this package accept either 4-byte (IPv4) or 16-byte (IPv6) slices as input.
Note that in this documentation, referring to an IP address as an IPv4 address or an IPv6 address is a semantic property of the address, not just the length of the byte slice: a 16-byte slice can still be an IPv4 address.
func IPv4(a, b, c, d byte) IP
IPv4 returns the IP address (in 16-byte form) of the IPv4 address a.b.c.d.
func ParseCIDR(s string) (IP, *IPNet, error)
ParseCIDR parses s as a CIDR notation IP address and mask, like "192.168.100.1/24" or "2001:DB8::/48", as defined in RFC 4632 and RFC 4291.
It returns the IP address and the network implied by the IP and mask. For example, ParseCIDR("192.168.100.1/16") returns the IP address 192.168.100.1 and the network 192.168.0.0/16.
func ParseIP(s string) IP
ParseIP parses s as an IP address, returning the result. The string s can be in dotted decimal ("74.125.19.99") or IPv6 ("2001:4860:0:2001::68") form. If s is not a valid textual representation of an IP address, ParseIP returns nil.
func (ip IP) DefaultMask() IPMask
DefaultMask returns the default IP mask for the IP address ip. Only IPv4 addresses have default masks; DefaultMask returns nil if ip is not a valid IPv4 address.
func (ip IP) Equal(x IP) bool
Equal reports whether ip and x are the same IP address. An IPv4 address and that same address in IPv6 form are considered to be equal.
func (ip IP) IsGlobalUnicast() bool
IsGlobalUnicast reports whether ip is a global unicast address.
func (ip IP) IsInterfaceLocalMulticast() bool
IsInterfaceLocalMulticast reports whether ip is an interface-local multicast address.
func (ip IP) IsLinkLocalMulticast() bool
IsLinkLocalMulticast reports whether ip is a link-local multicast address.
func (ip IP) IsLinkLocalUnicast() bool
IsLinkLocalUnicast reports whether ip is a link-local unicast address.
func (ip IP) IsLoopback() bool
IsLoopback reports whether ip is a loopback address.
func (ip IP) IsMulticast() bool
IsMulticast reports whether ip is a multicast address.
func (ip IP) IsUnspecified() bool
IsUnspecified reports whether ip is an unspecified address.
func (ip IP) MarshalText() ([]byte, error)
MarshalText implements the encoding.TextMarshaler interface. The encoding is the same as returned by String.
func (ip IP) Mask(mask IPMask) IP
Mask returns the result of masking the IP address ip with mask.
func (ip IP) String() string
String returns the string form of the IP address ip. If the address is an IPv4 address, the string representation is dotted decimal ("74.125.19.99"). Otherwise the representation is IPv6 ("2001:4860:0:2001::68").
func (ip IP) To16() IP
To16 converts the IP address ip to a 16-byte representation. If ip is not an IP address (it is the wrong length), To16 returns nil.
func (ip IP) To4() IP
To4 converts the IPv4 address ip to a 4-byte representation. If ip is not an IPv4 address, To4 returns nil.
func (ip *IP) UnmarshalText(text []byte) error
UnmarshalText implements the encoding.TextUnmarshaler interface. The IP address is expected in a form accepted by ParseIP.
type IPAddr struct {
IP IP
Zone string // IPv6 scoped addressing zone
}
IPAddr represents the address of an IP end point.
func ResolveIPAddr(net, addr string) (*IPAddr, error)
ResolveIPAddr parses addr as an IP address of the form "host" or "ipv6-host%zone" and resolves the domain name on the network net, which must be "ip", "ip4" or "ip6".
func (a *IPAddr) Network() string
Network returns the address's network name, "ip".
func (a *IPAddr) String() string
type IPConn struct {
// contains filtered or unexported fields
}
IPConn is the implementation of the Conn and PacketConn interfaces for IP network connections.
func DialIP(netProto string, laddr, raddr *IPAddr) (*IPConn, error)
DialIP connects to the remote address raddr on the network protocol netProto, which must be "ip", "ip4", or "ip6" followed by a colon and a protocol number or name.
func ListenIP(netProto string, laddr *IPAddr) (*IPConn, error)
ListenIP listens for incoming IP packets addressed to the local address laddr. The returned connection's ReadFrom and WriteTo methods can be used to receive and send IP packets with per-packet addressing.
func (c *IPConn) Close() error
Close closes the connection.
func (c *IPConn) File() (f *os.File, err error)
File sets the underlying os.File to blocking mode and returns a copy. It is the caller's responsibility to close f when finished. Closing c does not affect f, and closing f does not affect c.
The returned os.File's file descriptor is different from the connection's. Attempting to change properties of the original using this duplicate may or may not have the desired effect.
func (c *IPConn) LocalAddr() Addr
LocalAddr returns the local network address. The Addr returned is shared by all invocations of LocalAddr, so do not modify it.
func (c *IPConn) Read(b []byte) (int, error)
Read implements the Conn Read method.
func (c *IPConn) ReadFrom(b []byte) (int, Addr, error)
ReadFrom implements the PacketConn ReadFrom method.
func (c *IPConn) ReadFromIP(b []byte) (int, *IPAddr, error)
ReadFromIP reads an IP packet from c, copying the payload into b. It returns the number of bytes copied into b and the return address that was on the packet.
ReadFromIP can be made to time out and return an error with Timeout() == true after a fixed time limit; see SetDeadline and SetReadDeadline.
func (c *IPConn) ReadMsgIP(b, oob []byte) (n, oobn, flags int, addr *IPAddr, err error)
ReadMsgIP reads a packet from c, copying the payload into b and the associated out-of-band data into oob. It returns the number of bytes copied into b, the number of bytes copied into oob, the flags that were set on the packet and the source address of the packet.
func (c *IPConn) RemoteAddr() Addr
RemoteAddr returns the remote network address. The Addr returned is shared by all invocations of RemoteAddr, so do not modify it.
func (c *IPConn) SetDeadline(t time.Time) error
SetDeadline implements the Conn SetDeadline method.
func (c *IPConn) SetReadBuffer(bytes int) error
SetReadBuffer sets the size of the operating system's receive buffer associated with the connection.
func (c *IPConn) SetReadDeadline(t time.Time) error
SetReadDeadline implements the Conn SetReadDeadline method.
func (c *IPConn) SetWriteBuffer(bytes int) error
SetWriteBuffer sets the size of the operating system's transmit buffer associated with the connection.
func (c *IPConn) SetWriteDeadline(t time.Time) error
SetWriteDeadline implements the Conn SetWriteDeadline method.
func (c *IPConn) Write(b []byte) (int, error)
Write implements the Conn Write method.
func (c *IPConn) WriteMsgIP(b, oob []byte, addr *IPAddr) (n, oobn int, err error)
WriteMsgIP writes a packet to addr via c, copying the payload from b and the associated out-of-band data from oob. It returns the number of payload and out-of-band bytes written.
func (c *IPConn) WriteTo(b []byte, addr Addr) (int, error)
WriteTo implements the PacketConn WriteTo method.
func (c *IPConn) WriteToIP(b []byte, addr *IPAddr) (int, error)
WriteToIP writes an IP packet to addr via c, copying the payload from b.
WriteToIP can be made to time out and return an error with Timeout() == true after a fixed time limit; see SetDeadline and SetWriteDeadline. On packet-oriented connections, write timeouts are rare.
type IPMask []byte
An IP mask is an IP address.
func CIDRMask(ones, bits int) IPMask
CIDRMask returns an IPMask consisting of `ones' 1 bits followed by 0s up to a total length of `bits' bits. For a mask of this form, CIDRMask is the inverse of IPMask.Size.
func IPv4Mask(a, b, c, d byte) IPMask
IPv4Mask returns the IP mask (in 4-byte form) of the IPv4 mask a.b.c.d.
func (m IPMask) Size() (ones, bits int)
Size returns the number of leading ones and total bits in the mask. If the mask is not in the canonical form--ones followed by zeros--then Size returns 0, 0.
func (m IPMask) String() string
String returns the hexadecimal form of m, with no punctuation.
type IPNet struct {
IP IP // network number
Mask IPMask // network mask
}
An IPNet represents an IP network.
func (n *IPNet) Contains(ip IP) bool
Contains reports whether the network includes ip.
func (n *IPNet) Network() string
Network returns the address's network name, "ip+net".
func (n *IPNet) String() string
String returns the CIDR notation of n like "192.168.100.1/24" or "2001:DB8::/48" as defined in RFC 4632 and RFC 4291. If the mask is not in the canonical form, it returns the string which consists of an IP address, followed by a slash character and a mask expressed as hexadecimal form with no punctuation like "192.168.100.1/c000ff00".
type Interface struct {
Index int // positive integer that starts at one, zero is never used
MTU int // maximum transmission unit
Name string // e.g., "en0", "lo0", "eth0.100"
HardwareAddr HardwareAddr // IEEE MAC-48, EUI-48 and EUI-64 form
Flags Flags // e.g., FlagUp, FlagLoopback, FlagMulticast
}
Interface represents a mapping between network interface name and index. It also represents network interface facility information.
func InterfaceByIndex(index int) (*Interface, error)
InterfaceByIndex returns the interface specified by index.
func InterfaceByName(name string) (*Interface, error)
InterfaceByName returns the interface specified by name.
func (ifi *Interface) Addrs() ([]Addr, error)
Addrs returns interface addresses for a specific interface.
func (ifi *Interface) MulticastAddrs() ([]Addr, error)
MulticastAddrs returns multicast, joined group addresses for a specific interface.
type InvalidAddrError string
func (e InvalidAddrError) Error() string
func (e InvalidAddrError) Temporary() bool
func (e InvalidAddrError) Timeout() bool
type Listener interface {
// Accept waits for and returns the next connection to the listener.
Accept() (Conn, error)
// Close closes the listener.
// Any blocked Accept operations will be unblocked and return errors.
Close() error
// Addr returns the listener's network address.
Addr() Addr
}
A Listener is a generic network listener for stream-oriented protocols.
Multiple goroutines may invoke methods on a Listener simultaneously.
▹ Example
func FileListener(f *os.File) (ln Listener, err error)
FileListener returns a copy of the network listener corresponding to the open file f. It is the caller's responsibility to close ln when finished. Closing ln does not affect f, and closing f does not affect ln.
func Listen(net, laddr string) (Listener, error)
Listen announces on the local network address laddr. The network net must be a stream-oriented network: "tcp", "tcp4", "tcp6", "unix" or "unixpacket". For TCP and UDP, the syntax of laddr is "host:port", like "127.0.0.1:8080". If host is omitted, as in ":8080", Listen listens on all available interfaces instead of just the interface with the given host address. See Dial for more details about address syntax.
type MX struct {
Host string
Pref uint16
}
An MX represents a single DNS MX record.
type NS struct {
Host string
}
An NS represents a single DNS NS record.
type OpError struct {
// Op is the operation which caused the error, such as
// "read" or "write".
Op string
// Net is the network type on which this error occurred,
// such as "tcp" or "udp6".
Net string
// For operations involving a remote network connection, like
// Dial, Read, or Write, Source is the corresponding local
// network address.
Source Addr
// Addr is the network address for which this error occurred.
// For local operations, like Listen or SetDeadline, Addr is
// the address of the local endpoint being manipulated.
// For operations involving a remote network connection, like
// Dial, Read, or Write, Addr is the remote address of that
// connection.
Addr Addr
// Err is the error that occurred during the operation.
Err error
}
OpError is the error type usually returned by functions in the net package. It describes the operation, network type, and address of an error.
func (e *OpError) Error() string
func (e *OpError) Temporary() bool
func (e *OpError) Timeout() bool
type PacketConn interface {
// ReadFrom reads a packet from the connection,
// copying the payload into b. It returns the number of
// bytes copied into b and the return address that
// was on the packet.
// ReadFrom can be made to time out and return
// an error with Timeout() == true after a fixed time limit;
// see SetDeadline and SetReadDeadline.
ReadFrom(b []byte) (n int, addr Addr, err error)
// WriteTo writes a packet with payload b to addr.
// WriteTo can be made to time out and return
// an error with Timeout() == true after a fixed time limit;
// see SetDeadline and SetWriteDeadline.
// On packet-oriented connections, write timeouts are rare.
WriteTo(b []byte, addr Addr) (n int, err error)
// Close closes the connection.
// Any blocked ReadFrom or WriteTo operations will be unblocked and return errors.
Close() error
// LocalAddr returns the local network address.
LocalAddr() Addr
// SetDeadline sets the read and write deadlines associated
// with the connection.
SetDeadline(t time.Time) error
// SetReadDeadline sets the deadline for future Read calls.
// If the deadline is reached, Read will fail with a timeout
// (see type Error) instead of blocking.
// A zero value for t means Read will not time out.
SetReadDeadline(t time.Time) error
// SetWriteDeadline sets the deadline for future Write calls.
// If the deadline is reached, Write will fail with a timeout
// (see type Error) instead of blocking.
// A zero value for t means Write will not time out.
// Even if write times out, it may return n > 0, indicating that
// some of the data was successfully written.
SetWriteDeadline(t time.Time) error
}
PacketConn is a generic packet-oriented network connection.
Multiple goroutines may invoke methods on a PacketConn simultaneously.
func FilePacketConn(f *os.File) (c PacketConn, err error)
FilePacketConn returns a copy of the packet network connection corresponding to the open file f. It is the caller's responsibility to close f when finished. Closing c does not affect f, and closing f does not affect c.
func ListenPacket(net, laddr string) (PacketConn, error)
ListenPacket announces on the local network address laddr. The network net must be a packet-oriented network: "udp", "udp4", "udp6", "ip", "ip4", "ip6" or "unixgram". For TCP and UDP, the syntax of laddr is "host:port", like "127.0.0.1:8080". If host is omitted, as in ":8080", ListenPacket listens on all available interfaces instead of just the interface with the given host address. See Dial for the syntax of laddr.
type ParseError struct {
// Type is the type of string that was expected, such as
// "IP address", "CIDR address".
Type string
// Text is the malformed text string.
Text string
}
A ParseError is the error type of literal network address parsers.
func (e *ParseError) Error() string
type SRV struct {
Target string
Port uint16
Priority uint16
Weight uint16
}
An SRV represents a single DNS SRV record.
type TCPAddr struct {
IP IP
Port int
Zone string // IPv6 scoped addressing zone
}
TCPAddr represents the address of a TCP end point.
func ResolveTCPAddr(net, addr string) (*TCPAddr, error)
ResolveTCPAddr parses addr as a TCP address of the form "host:port" or "[ipv6-host%zone]:port" and resolves a pair of domain name and port name on the network net, which must be "tcp", "tcp4" or "tcp6". A literal address or host name for IPv6 must be enclosed in square brackets, as in "[::1]:80", "[ipv6-host]:http" or "[ipv6-host%zone]:80".
func (a *TCPAddr) Network() string
Network returns the address's network name, "tcp".
func (a *TCPAddr) String() string
type TCPConn struct {
// contains filtered or unexported fields
}
TCPConn is an implementation of the Conn interface for TCP network connections.
func DialTCP(net string, laddr, raddr *TCPAddr) (*TCPConn, error)
DialTCP connects to the remote address raddr on the network net, which must be "tcp", "tcp4", or "tcp6". If laddr is not nil, it is used as the local address for the connection.
func (c *TCPConn) Close() error
Close closes the connection.
func (c *TCPConn) CloseRead() error
CloseRead shuts down the reading side of the TCP connection. Most callers should just use Close.
func (c *TCPConn) CloseWrite() error
CloseWrite shuts down the writing side of the TCP connection. Most callers should just use Close.
func (c *TCPConn) File() (f *os.File, err error)
File sets the underlying os.File to blocking mode and returns a copy. It is the caller's responsibility to close f when finished. Closing c does not affect f, and closing f does not affect c.
The returned os.File's file descriptor is different from the connection's. Attempting to change properties of the original using this duplicate may or may not have the desired effect.
func (c *TCPConn) LocalAddr() Addr
LocalAddr returns the local network address. The Addr returned is shared by all invocations of LocalAddr, so do not modify it.
func (c *TCPConn) Read(b []byte) (int, error)
Read implements the Conn Read method.
func (c *TCPConn) ReadFrom(r io.Reader) (int64, error)
ReadFrom implements the io.ReaderFrom ReadFrom method.
func (c *TCPConn) RemoteAddr() Addr
RemoteAddr returns the remote network address. The Addr returned is shared by all invocations of RemoteAddr, so do not modify it.
func (c *TCPConn) SetDeadline(t time.Time) error
SetDeadline implements the Conn SetDeadline method.
func (c *TCPConn) SetKeepAlive(keepalive bool) error
SetKeepAlive sets whether the operating system should send keepalive messages on the connection.
func (c *TCPConn) SetKeepAlivePeriod(d time.Duration) error
SetKeepAlivePeriod sets period between keep alives.
func (c *TCPConn) SetLinger(sec int) error
SetLinger sets the behavior of Close on a connection which still has data waiting to be sent or to be acknowledged.
If sec < 0 (the default), the operating system finishes sending the data in the background.
If sec == 0, the operating system discards any unsent or unacknowledged data.
If sec > 0, the data is sent in the background as with sec < 0. On some operating systems after sec seconds have elapsed any remaining unsent data may be discarded.
func (c *TCPConn) SetNoDelay(noDelay bool) error
SetNoDelay controls whether the operating system should delay packet transmission in hopes of sending fewer packets (Nagle's algorithm). The default is true (no delay), meaning that data is sent as soon as possible after a Write.
func (c *TCPConn) SetReadBuffer(bytes int) error
SetReadBuffer sets the size of the operating system's receive buffer associated with the connection.
func (c *TCPConn) SetReadDeadline(t time.Time) error
SetReadDeadline implements the Conn SetReadDeadline method.
func (c *TCPConn) SetWriteBuffer(bytes int) error
SetWriteBuffer sets the size of the operating system's transmit buffer associated with the connection.
func (c *TCPConn) SetWriteDeadline(t time.Time) error
SetWriteDeadline implements the Conn SetWriteDeadline method.
func (c *TCPConn) Write(b []byte) (int, error)
Write implements the Conn Write method.
type TCPListener struct {
// contains filtered or unexported fields
}
TCPListener is a TCP network listener. Clients should typically use variables of type Listener instead of assuming TCP.
func ListenTCP(net string, laddr *TCPAddr) (*TCPListener, error)
ListenTCP announces on the TCP address laddr and returns a TCP listener. Net must be "tcp", "tcp4", or "tcp6". If laddr has a port of 0, ListenTCP will choose an available port. The caller can use the Addr method of TCPListener to retrieve the chosen address.
func (l *TCPListener) Accept() (Conn, error)
Accept implements the Accept method in the Listener interface; it waits for the next call and returns a generic Conn.
func (l *TCPListener) AcceptTCP() (*TCPConn, error)
AcceptTCP accepts the next incoming call and returns the new connection.
func (l *TCPListener) Addr() Addr
Addr returns the listener's network address, a *TCPAddr. The Addr returned is shared by all invocations of Addr, so do not modify it.
func (l *TCPListener) Close() error
Close stops listening on the TCP address. Already Accepted connections are not closed.
func (l *TCPListener) File() (f *os.File, err error)
File returns a copy of the underlying os.File, set to blocking mode. It is the caller's responsibility to close f when finished. Closing l does not affect f, and closing f does not affect l.
The returned os.File's file descriptor is different from the connection's. Attempting to change properties of the original using this duplicate may or may not have the desired effect.
func (l *TCPListener) SetDeadline(t time.Time) error
SetDeadline sets the deadline associated with the listener. A zero time value disables the deadline.
type UDPAddr struct {
IP IP
Port int
Zone string // IPv6 scoped addressing zone
}
UDPAddr represents the address of a UDP end point.
func ResolveUDPAddr(net, addr string) (*UDPAddr, error)
ResolveUDPAddr parses addr as a UDP address of the form "host:port" or "[ipv6-host%zone]:port" and resolves a pair of domain name and port name on the network net, which must be "udp", "udp4" or "udp6". A literal address or host name for IPv6 must be enclosed in square brackets, as in "[::1]:80", "[ipv6-host]:http" or "[ipv6-host%zone]:80".
func (a *UDPAddr) Network() string
Network returns the address's network name, "udp".
func (a *UDPAddr) String() string
type UDPConn struct {
// contains filtered or unexported fields
}
UDPConn is the implementation of the Conn and PacketConn interfaces for UDP network connections.
func DialUDP(net string, laddr, raddr *UDPAddr) (*UDPConn, error)
DialUDP connects to the remote address raddr on the network net, which must be "udp", "udp4", or "udp6". If laddr is not nil, it is used as the local address for the connection.
func ListenMulticastUDP(network string, ifi *Interface, gaddr *UDPAddr) (*UDPConn, error)
ListenMulticastUDP listens for incoming multicast UDP packets addressed to the group address gaddr on the interface ifi. Network must be "udp", "udp4" or "udp6". ListenMulticastUDP uses the system-assigned multicast interface when ifi is nil, although this is not recommended because the assignment depends on platforms and sometimes it might require routing configuration.
ListenMulticastUDP is just for convenience of simple, small applications. There are golang.org/x/net/ipv4 and golang.org/x/net/ipv6 packages for general purpose uses.
func ListenUDP(net string, laddr *UDPAddr) (*UDPConn, error)
ListenUDP listens for incoming UDP packets addressed to the local address laddr. Net must be "udp", "udp4", or "udp6". If laddr has a port of 0, ListenUDP will choose an available port. The LocalAddr method of the returned UDPConn can be used to discover the port. The returned connection's ReadFrom and WriteTo methods can be used to receive and send UDP packets with per-packet addressing.
func (c *UDPConn) Close() error
Close closes the connection.
func (c *UDPConn) File() (f *os.File, err error)
File sets the underlying os.File to blocking mode and returns a copy. It is the caller's responsibility to close f when finished. Closing c does not affect f, and closing f does not affect c.
The returned os.File's file descriptor is different from the connection's. Attempting to change properties of the original using this duplicate may or may not have the desired effect.
func (c *UDPConn) LocalAddr() Addr
LocalAddr returns the local network address. The Addr returned is shared by all invocations of LocalAddr, so do not modify it.
func (c *UDPConn) Read(b []byte) (int, error)
Read implements the Conn Read method.
func (c *UDPConn) ReadFrom(b []byte) (int, Addr, error)
ReadFrom implements the PacketConn ReadFrom method.
func (c *UDPConn) ReadFromUDP(b []byte) (int, *UDPAddr, error)
ReadFromUDP reads a UDP packet from c, copying the payload into b. It returns the number of bytes copied into b and the return address that was on the packet.
ReadFromUDP can be made to time out and return an error with Timeout() == true after a fixed time limit; see SetDeadline and SetReadDeadline.
func (c *UDPConn) ReadMsgUDP(b, oob []byte) (n, oobn, flags int, addr *UDPAddr, err error)
ReadMsgUDP reads a packet from c, copying the payload into b and the associated out-of-band data into oob. It returns the number of bytes copied into b, the number of bytes copied into oob, the flags that were set on the packet and the source address of the packet.
func (c *UDPConn) RemoteAddr() Addr
RemoteAddr returns the remote network address. The Addr returned is shared by all invocations of RemoteAddr, so do not modify it.
func (c *UDPConn) SetDeadline(t time.Time) error
SetDeadline implements the Conn SetDeadline method.
func (c *UDPConn) SetReadBuffer(bytes int) error
SetReadBuffer sets the size of the operating system's receive buffer associated with the connection.
func (c *UDPConn) SetReadDeadline(t time.Time) error
SetReadDeadline implements the Conn SetReadDeadline method.
func (c *UDPConn) SetWriteBuffer(bytes int) error
SetWriteBuffer sets the size of the operating system's transmit buffer associated with the connection.
func (c *UDPConn) SetWriteDeadline(t time.Time) error
SetWriteDeadline implements the Conn SetWriteDeadline method.
func (c *UDPConn) Write(b []byte) (int, error)
Write implements the Conn Write method.
func (c *UDPConn) WriteMsgUDP(b, oob []byte, addr *UDPAddr) (n, oobn int, err error)
WriteMsgUDP writes a packet to addr via c if c isn't connected, or to c's remote destination address if c is connected (in which case addr must be nil). The payload is copied from b and the associated out-of-band data is copied from oob. It returns the number of payload and out-of-band bytes written.
func (c *UDPConn) WriteTo(b []byte, addr Addr) (int, error)
WriteTo implements the PacketConn WriteTo method.
func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (int, error)
WriteToUDP writes a UDP packet to addr via c, copying the payload from b.
WriteToUDP can be made to time out and return an error with Timeout() == true after a fixed time limit; see SetDeadline and SetWriteDeadline. On packet-oriented connections, write timeouts are rare.
type UnixAddr struct {
Name string
Net string
}
UnixAddr represents the address of a Unix domain socket end point.
func ResolveUnixAddr(net, addr string) (*UnixAddr, error)
ResolveUnixAddr parses addr as a Unix domain socket address. The string net gives the network name, "unix", "unixgram" or "unixpacket".
func (a *UnixAddr) Network() string
Network returns the address's network name, "unix", "unixgram" or "unixpacket".
func (a *UnixAddr) String() string
type UnixConn struct {
// contains filtered or unexported fields
}
UnixConn is an implementation of the Conn interface for connections to Unix domain sockets.
func DialUnix(net string, laddr, raddr *UnixAddr) (*UnixConn, error)
DialUnix connects to the remote address raddr on the network net, which must be "unix", "unixgram" or "unixpacket". If laddr is not nil, it is used as the local address for the connection.
func ListenUnixgram(net string, laddr *UnixAddr) (*UnixConn, error)
ListenUnixgram listens for incoming Unix datagram packets addressed to the local address laddr. The network net must be "unixgram". The returned connection's ReadFrom and WriteTo methods can be used to receive and send packets with per-packet addressing.
func (c *UnixConn) Close() error
Close closes the connection.
func (c *UnixConn) CloseRead() error
CloseRead shuts down the reading side of the Unix domain connection. Most callers should just use Close.
func (c *UnixConn) CloseWrite() error
CloseWrite shuts down the writing side of the Unix domain connection. Most callers should just use Close.
func (c *UnixConn) File() (f *os.File, err error)
File sets the underlying os.File to blocking mode and returns a copy. It is the caller's responsibility to close f when finished. Closing c does not affect f, and closing f does not affect c.
The returned os.File's file descriptor is different from the connection's. Attempting to change properties of the original using this duplicate may or may not have the desired effect.
func (c *UnixConn) LocalAddr() Addr
LocalAddr returns the local network address. The Addr returned is shared by all invocations of LocalAddr, so do not modify it.
func (c *UnixConn) Read(b []byte) (int, error)
Read implements the Conn Read method.
func (c *UnixConn) ReadFrom(b []byte) (int, Addr, error)
ReadFrom implements the PacketConn ReadFrom method.
func (c *UnixConn) ReadFromUnix(b []byte) (int, *UnixAddr, error)
ReadFromUnix reads a packet from c, copying the payload into b. It returns the number of bytes copied into b and the source address of the packet.
ReadFromUnix can be made to time out and return an error with Timeout() == true after a fixed time limit; see SetDeadline and SetReadDeadline.
func (c *UnixConn) ReadMsgUnix(b, oob []byte) (n, oobn, flags int, addr *UnixAddr, err error)
ReadMsgUnix reads a packet from c, copying the payload into b and the associated out-of-band data into oob. It returns the number of bytes copied into b, the number of bytes copied into oob, the flags that were set on the packet, and the source address of the packet.
func (c *UnixConn) RemoteAddr() Addr
RemoteAddr returns the remote network address. The Addr returned is shared by all invocations of RemoteAddr, so do not modify it.
func (c *UnixConn) SetDeadline(t time.Time) error
SetDeadline implements the Conn SetDeadline method.
func (c *UnixConn) SetReadBuffer(bytes int) error
SetReadBuffer sets the size of the operating system's receive buffer associated with the connection.
func (c *UnixConn) SetReadDeadline(t time.Time) error
SetReadDeadline implements the Conn SetReadDeadline method.
func (c *UnixConn) SetWriteBuffer(bytes int) error
SetWriteBuffer sets the size of the operating system's transmit buffer associated with the connection.
func (c *UnixConn) SetWriteDeadline(t time.Time) error
SetWriteDeadline implements the Conn SetWriteDeadline method.
func (c *UnixConn) Write(b []byte) (int, error)
Write implements the Conn Write method.
func (c *UnixConn) WriteMsgUnix(b, oob []byte, addr *UnixAddr) (n, oobn int, err error)
WriteMsgUnix writes a packet to addr via c, copying the payload from b and the associated out-of-band data from oob. It returns the number of payload and out-of-band bytes written.
func (c *UnixConn) WriteTo(b []byte, addr Addr) (n int, err error)
WriteTo implements the PacketConn WriteTo method.
func (c *UnixConn) WriteToUnix(b []byte, addr *UnixAddr) (int, error)
WriteToUnix writes a packet to addr via c, copying the payload from b.
WriteToUnix can be made to time out and return an error with Timeout() == true after a fixed time limit; see SetDeadline and SetWriteDeadline. On packet-oriented connections, write timeouts are rare.
type UnixListener struct {
// contains filtered or unexported fields
}
UnixListener is a Unix domain socket listener. Clients should typically use variables of type Listener instead of assuming Unix domain sockets.
func ListenUnix(net string, laddr *UnixAddr) (*UnixListener, error)
ListenUnix announces on the Unix domain socket laddr and returns a Unix listener. The network net must be "unix" or "unixpacket".
func (l *UnixListener) Accept() (c Conn, err error)
Accept implements the Accept method in the Listener interface; it waits for the next call and returns a generic Conn.
func (l *UnixListener) AcceptUnix() (*UnixConn, error)
AcceptUnix accepts the next incoming call and returns the new connection.
func (l *UnixListener) Addr() Addr
Addr returns the listener's network address. The Addr returned is shared by all invocations of Addr, so do not modify it.
func (l *UnixListener) Close() error
Close stops listening on the Unix address. Already accepted connections are not closed.
func (l *UnixListener) File() (f *os.File, err error)
File returns a copy of the underlying os.File, set to blocking mode. It is the caller's responsibility to close f when finished. Closing l does not affect f, and closing f does not affect l.
The returned os.File's file descriptor is different from the connection's. Attempting to change properties of the original using this duplicate may or may not have the desired effect.
func (l *UnixListener) SetDeadline(t time.Time) error
SetDeadline sets the deadline associated with the listener. A zero time value disables the deadline.
type UnknownNetworkError string
func (e UnknownNetworkError) Error() string
func (e UnknownNetworkError) Temporary() bool
func (e UnknownNetworkError) Timeout() bool
On every POSIX platform, reads from the "ip4" network using the ReadFrom or ReadFromIP method might not return a complete IPv4 packet, including its header, even if there is space available. This can occur even in cases where Read or ReadMsgIP could return a complete packet. For this reason, it is recommended that you do not uses these methods if it is important to receive a full packet.
The Go 1 compatibility guidelines make it impossible for us to change the behavior of these methods; use Read or ReadMsgIP instead.
On DragonFly BSD and OpenBSD, listening on the "tcp" and "udp" networks does not listen for both IPv4 and IPv6 connections. This is due to the fact that IPv4 traffic will not be routed to an IPv6 socket - two separate sockets are required if both address families are to be supported. See inet6(4) for details.
| Name | Synopsis |
|---|---|
| .. | |
| http | Package http provides HTTP client and server implementations. |
| cgi | Package cgi implements CGI (Common Gateway Interface) as specified in RFC 3875. |
| cookiejar | Package cookiejar implements an in-memory RFC 6265-compliant http.CookieJar. |
| fcgi | Package fcgi implements the FastCGI protocol. |
| httptest | Package httptest provides utilities for HTTP testing. |
| httputil | Package httputil provides HTTP utility functions, complementing the more common ones in the net/http package. |
| pprof | Package pprof serves via its HTTP server runtime profiling data in the format expected by the pprof visualization tool. |
| Package mail implements parsing of mail messages. | |
| rpc | Package rpc provides access to the exported methods of an object across a network or other I/O connection. |
| jsonrpc | Package jsonrpc implements a JSON-RPC ClientCodec and ServerCodec for the rpc package. |
| smtp | Package smtp implements the Simple Mail Transfer Protocol as defined in RFC 5321. |
| textproto | Package textproto implements generic support for text-based request/response protocols in the style of HTTP, NNTP, and SMTP. |
| url | Package url parses URLs and implements query escaping. |