Obtain single instance for this host.

Returns the NSMessagePort instance registered for the specified name if it exists on the local host.

Returns the port registered for the specified name (if it exists).
The host must be an empty string or nil, since NSMessagePort instances on other hosts are inaccessible from the current host.

Returns the default port name server for the process.
This is a nameserver for host-local connections private to the current user. If you with to create public connections or connections to other hosts, you must use [NSSocketPortNameServer +sharedInstance] instead.

This default behavior may be altered by setting the NSPortIsMessagePort user default to NO, in which case an NSSocketPortNameServer will be used as the default system name server and you will have to use [NSMessagePortNameServer +sharedInstance] for host-local, private connections.

Looks up the port with the specified name on the local host and returns it or nil if no port is found with that name.
Different nameservers have different namespaces appropriate to the type of port they deal with, so failing to find a named port with one nameserver does not guarantee that a port does with that name does not exist.
This is a convenience method calling -portForName:onHost: with a nil host argument.

Looks up the port with the specified name on host and returns it or nil if no port is found with that name.
Different nameservers have different namespaces appropriate to the type of port they deal with, so failing to find a named port with one nameserver does not guarantee that a port does with that name does not exist.

Registers port with the supplied name, so that other processes can look it up to contact it. A port may be registered with more than one name by making multiple calls to this method.
Returns YES on success, NO otherwise.
The common cause for failure is that another port is already registered with the name. Raises NSInvalidArgumentException if given bad arguments.

Removes any port registration for the supplied name (whether registered in the current process or another).
The common cause for failure is that no port is registered with the name.
Raises NSInvalidArgumentException if given bad arguments.

Returns the shared name server object for NSSocketPort objects.

Concrete implementation of [NSPortNameServer -portForName:onHost:]
Looks up and returns a port with the specified name and host.
If host is nil or an empty string, this performs a lookup for a port on the current host.
If host is an asterisk ('*') then the lookup returns the first port found with the specified name on any machine on the local network.
Returns nil if no matching port could be found.

Concrete implementation of [NSPortNameServer -registerPort:forName:]
Registers the port with the specified name such that it is available on all the IP addresses of the host on which the process is running.
Returns YES on success, NO on failure (eg the name is already in use or there is a problem registering for some reason).

Concrete implementation of [NSPortNameServer -removePortForName:]
Unregisters the specified name from any associated port on the local host.
Returns YES on success, NO on failure.