python 2.7 socket module

AF_INET

A pair (host, port) is used for the ________address family, where host is a string representing either a hostname in Internet domain notation like 'google.com' or an IPv4 address like '100.50.200.5', and port is an integer.

AF_UNIX

A single string is used for the __________ address family

accept()

Accept a connection. The socket must be bound to an address and listening for connections. The return value is a pair (conn, address) where conn is a new socket object usable to send and receive data on the connection, and address is the address bound to the socket on the other end of the connection.

bind(address)

Bind the socket to address. The socket must not already be bound. (The format of address depends on the address family — see above.)

socketpair([family[, type[, proto]]])

Build a pair of connected socket objects using the given address family, socket type, and protocol number. Address family, socket type, and protocol number are as for the socket() function above. The default family is AF_UNIX if defined on the platform; otherwise, the default is AF_INET. Availability: Unix.

close()

Close the socket. All future operations on the socket object will fail. The remote end will receive no more data (after queued data is flushed). Sockets are automatically closed when they are garbage-collected.

create_connection(address[, timeout[, source_address]])

Connect to a TCP service listening on the Internet address (a 2-tuple (host, port)), and return the socket object. This is a higher-level function than socket.connect(): if host is a non-numeric hostname, it will try to resolve it for both AF_INET and AF_INET6, and then try to connect to all possible addresses in turn until a connection succeeds. This makes it easy to write clients that are compatible to both IPv4 and IPv6.

connect(address)

Connect to a remote socket at address. (The format of address depends on the address family — see above.)

socket([family[, type[, proto]]])

Create a new socket using the given address family, socket type and protocol number. The address family should be AF_INET (the default), AF_INET6 or AF_UNIX. The socket type should be SOCK_STREAM (the default), SOCK_DGRAM or perhaps one of the other SOCK_ constants. The protocol number is usually zero and may be omitted in that case.

AF_INET6

For ________ address family, a four-tuple (host, port, flowinfo, scopeid) is used.

connect_ex(address)

Like connect(address), but return an error indicator instead of raising an exception for errors returned by the C-level connect() call

listen(backlog)

Listen for connections made to the socket. The backlog argument specifies the maximum number of queued connections and should be at least 0; the maximum value is system-dependent (usually 5), the minimum value is forced to 0.

recvfrom(bufsize[, flags])

Receive data from the socket. The return value is a pair (string, address) where string is a string representing the data received and address is the address of the socket sending the data.

recv(bufsize[, flags])

Receive data from the socket. The return value is a string representing the data received. The maximum amount of data to be received at once is specified by bufsize. See the Unix manual page recv(2) for the meaning of the optional argument flags; it defaults to zero.

gethostname()

Return a triple (hostname, aliaslist, ipaddrlist) where hostname is the primary host name responding to the given ip_address, aliaslist is a (possibly empty) list of alternative host names for the same address, and ipaddrlist is a list of IPv4/v6 addresses for the same interface on the same host (most likely containing only a single address). To find the fully qualified domain name, use the function getfqdn(). gethostbyaddr() supports both IPv4 and IPv6.

getdefaulttimeout()

Return the default timeout in seconds (float) for new socket objects. A value of None indicates that new socket objects have no timeout. When the socket module is first imported, the default is None.

getpeername()

Return the remote address to which the socket is connected. This is useful to find out the port number of a remote IPv4/v6 socket, for instance. (The format of the address returned depends on the address family — see above.) On some systems this function is not supported.

fileno()

Return the socket's file descriptor (a small integer). This is useful with select.select().

getsockname()

Return the socket's own address. This is useful to find out the port number of an IPv4/v6 socket, for instance. (The format of the address returned depends on the address family — see above.)

getsockopt(level, optname[, buflen])

Return the value of the given socket option (see the Unix man page getsockopt(2)). The needed symbolic constants (SO_* etc.) are defined in this module. If buflen is absent, an integer option is assumed and its integer value is returned by the function. If buflen is present, it specifies the maximum length of the buffer used to receive the option in, and this buffer is returned as a string. It is up to the caller to decode the contents of the buffer

send(string[, flags])

Send data to the socket. The socket must be connected to a remote socket. The optional flags argument has the same meaning as for recv() above. Returns the number of bytes sent. Applications are responsible for checking that all data has been sent; if only some of the data was transmitted, the application needs to attempt delivery of the remaining data.

setdefaulttimeout(timeout)

Set the default timeout in seconds (float) for new socket objects. A value of None indicates that new socket objects have no timeout. When the socket module is first imported, the default is None.

family

The socket family

proto

The socket protocol

type

The socket type

SOCK_STREAM, SOCK_DGRAM, SOCK_RAW, SOCK_RDM, SOCK_SEQPACKET

These constants represent the address (and protocol) families, used for the first argument to socket(). If the AF_UNIX constant is not defined then this protocol is unsupported.

SO_* socket.SOMAXCONN MSG_* SOL_* IPPROTO_* IPPORT_* INADDR_* IP_* IPV6_* EAI_* AI_* NI_* TCP_*

These constants represent the socket types, used for the second argument to socket(). (Only SOCK_STREAM and SOCK_DGRAM appear to be generally useful.)

herror

This exception is raised for address-related errors

gaierror

This exception is raised for address-related errors, for getaddrinfo() and getnameinfo(). The accompanying value is a pair (error, string) representing an error returned by a library call. string represents the description of error, as returned by the gai_strerror() C function. The error value will match one of the EAI_* constants defined in this module.

error

This exception is raised for socket-related errors. The accompanying value is either a string telling what went wrong or a pair (errno, string) representing an error returned by a system call

timeout

This exception is raised when a timeout occurs on a socket which has had timeouts enabled via a prior call to settimeout(). The accompanying value is a string whose value is currently always "timed out".

SocketType

This is a Python type object that represents the socket object type. It is the same as type(socket(...)).

gethostbyname_ex(hostname)

Translate a host name to IPv4 address format, extended interface. Return a triple (hostname, aliaslist, ipaddrlist) where hostname is the primary host name responding to the given ip_address, aliaslist is a (possibly empty) list of alternative host names for the same address, and ipaddrlist is a list of IPv4 addresses for the same interface on the same host (often but not always a single address).

gethostbyname(hostname)

Translate a host name to IPv4 address format. The IPv4 address is returned as a string, such as '100.50.200.5'.

getservbyport

Translate an Internet port number and protocol name to a service name for that service. The optional protocol name, if given, should be 'tcp' or 'udp', otherwise any protocol will match.

getservbyname

Translate an Internet service name and protocol name to a port number for that service. The optional protocol name, if given, should be 'tcp' or 'udp', otherwise any protocol will match.

getaddrinfo(host, port[, family[, socktype[, proto[, flags]]]])

Translate the host/port argument into a sequence of 5-tuples that contain all the necessary arguments for creating a socket connected to that service. host is a domain name, a string representation of an IPv4/v6 address or None. port is a string service name such as 'http', a numeric port number or None. The function returns a list of 5-tuples with the following structure: (family, socktype, proto, canonname, sockaddr)