socket class is used to create low level networking interface. It is using some operating system socket APIs, so some behaviors may be platform dependent.
- AF_UNIX socket - Address bound to a file system node and it's represented as a string(uses UTF-8 encoding).
- AF_INET - Address uses a pair (host, port), here host is a string represents either a host name in Internet domain example 'google.com' or an IPv4 address example '10.20.160.61' and port is an integer number.
- AF_INET6 - Address is a tuple (host, port, flow_info, scope_id), here host and port is like same as mentioned above point, flow_info and scope_id are optional, these denote sin6_flowinfo and sin6_scope_id members in struct sockaddr_in6 in C.
- AF_NETLINK - Address is a pair (pid, groups).
- AF_TIPC - TIPC is an open, non-IP based networked protocol
- AF_BLUETOOTH - supports protocols like BTPROTO_L2CAP, BTPROTO_RFCOMM, BTPROTO_HCI and BTPROTO_SCO.
- AF_ALG - Linux-only socket based interface to Kernel cryptography.
Some socket constants
Some constants are related to mention address family.
These constants are related to socket types.
- socket.error - This class was made an alias of OSError.
- socket.herror - subclass of OSError exception and raised for address-related errors when calling gethostbyname_ex() and gethostbyaddr() functions
- socket.gaierror - subclass of OSError exception and raised for address-related errors when calling getaddrinfo() and getnameinfo()
- socket.timeout - subclass of OSError exception and raised when a timeout occurs on a socket settimeout()
- soket.socket - creating socket object.
socket.socket(family=AF_INET, type=SOCK_STREAM, protocol_number=0, file_number=None)
- socket.socketpair - creating a pair of connected socket objects.
socket.socketpair([family[, type[, protocol_number]]])
- socket.create_connection - Connecting TCP service listening on the address (tuple (host, port)) and return the socket object.
socket.create_connection(address[, timeout[, source_address]])
- socket.getaddrinfo - function returns a list of tuples (family, type, protocol number, canonical name, socket address)
socket.getaddrinfo(host, port, family=0, type=0, proto=0, flags=0)
- socket.gethostbyname - gets IPv4 address as a string from host name.
- socket.gethostname - gets the hostname of the local machine.
- socket.gethostbyaddr - get the host name (host_name, alias_name_list, ip_address_list) for given ip address where hostname is the primary host name.
Python program to get ip address of internet domain name.
port = 80
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
print "Socket object is created"
host_ip = socket.gethostbyname('www.codingpointer.com')
except (socket.error, socket.gaierror) as ex:
print "socket error: %s" %(ex)
# connecting server
print "Connected codingpointer.com on port == %s" %(host_ip)
Python Programming Language Examples