The Yoix^® Scripting Language

Several incompatible changes introduced in release 1.4.0 of the Yoix interpreter will affect older applications that used the DatagramSocket, ServerSocket, or Socket types. Take a look at the description of the obsolete port field if you have an old application that is having trouble using a ServerSocket. The fields in a ServerSocket are:

accept([Dictionary init])	A Builtin that waits for the next client to connect to the serversocket's localaddress and localport and returns a Socket that can be used to communicate with that client or NULL if accept timed out, was interupted, or encountered any other kind of error. accept automatically activates the serversocket if it is not alive. The optional init argument can be used to initialize fields in the Socket that accept returns.
alive	An int that is 1 if the serversocket has been activated and 0 otherwise. Storing 1 in alive activates the serversocket, which automatically binds it to localaddress and localport. Calling the accept built-in also activate the serversocket.
backlog	An int specifying the maximum queue length that the serversocket will support when connection requests come in faster than the server can handle. Changing backlog while a serversocket is alive is not allowed and will result in an invalidaccess error.
localaddress	A String that identifies network interfaces on the local machine that the serversocket will bind to when it is activated. The value should be the name of a network interface (e.g., eth0 or lo), an IP address, a host name that can be resolved by DNS, or NULL (the default), which means the wildcard address that usually matches any local address. A serversocket that is bound to localaddress and localport will only accept connections that are directed to that address and port. Reading localaddress when the serversocket is alive always returns an IP address. Changing localaddress while a serversocket is alive is not allowed and will result in an invalidaccess error.
localname	A read-only String that is the name of the host associated with the IP address read from localaddress when the serversocket is alive and NULL when it is not alive.
localport	An int that identifies the port that the serversocket will bind to when it is activated. The value should be an integer between 0 (the default) and 65535, inclusive. A localport that is 0 means the system should pick an ephemeral port, which usually does not make much sense for a server. A serversocket that is bound to localaddress and localport will only accept connections that are directed to that address and port. Changing localport while a serversocket is alive is not allowed and will result in an invalidaccess error.
port	An obsolete field that was replaced by localport in the 1.4.0 release of the Yoix interpreter.
receivebuffersize	An int that is the size, in bytes, of the receive buffer used by sockets that are created by this serversocket, which will also be the size of the TCP receive window that is advertised to the remote peer. Reading returns the actual buffer size if the serversocket is alive, or the size that will be requested from the operating system when it is activated. Writing requests buffers of a certain size, however the request may or may not be honored by the operating system. Storing a negative number in receivebuffersize is ignored and makes no changes to the current setting. Buffers larger than 64K bytes are allowed but must be requested before the serversocket is activated, otherwise remote peers of the sockets created by this serversocket may not be able to take advantage of the extra space.
reuseaddress	An int that is 1 if another socket can be bound to the same localaddress and localport pair immediately after this serversocket is closed and 0 otherwise. Storing 0 in alive closes the serversocket, which puts it in a timeout state (officially called the TIME_WAIT state) that can last several minutes. During that time any attempt to reuse localaddress and localport by any process on your system will fail unless resueaddress was 1 when the serversocket was activated. Changing reuseaddress while the serversocket is alive is allowed, but the results are not well defined.
timeout	A double that specifies how long the accept built-in will wait, in seconds, before giving up. A zero value disables timeouts and means accept will wait forever. Writing is allowed, but does not affect an accept call that has already started. Storing a negative number in timeout is ignored and makes no changes to the current setting.

Several permanent fields have not been documented and should not be used in Yoix applications. If you look closely you may notice that some fields in a ServerSocket are initialized with values, like -1, that the documentation says are explicitly ignored. It is an approach that lets Java (and your operating system) pick values when the serversocket is activated for fields that you choose not to initialize.

Example:	The following program, import yoix.*.*; Socket client; ServerSocket ss = { int localport = 8888; }; func(arg) { printf("Called func: client=%O\n", arg); } do { printf("accepting connections on %d\n", ss.localport); if ((client = ss.accept()) != NULL) { Thread handler; handler.queue(func, client); } } while (ss.alive); does not do any useful work, but it runs and you can easily verify (e.g., by using telnet) that it really does start a new thread that executes function func whenever a client connects to port 8888. See the Socket documentation for another example.
See Also:	DatagramSocket, getAddress, getAllByName, getHostAddress, getHostName, getInterfaceAddress, getInterfaceAddresses, isAnyLocalAddress, isLinkLocalAddress, isLoopbackAddress, isMulticastAddress, isSiteLocalAddress, MulticastSocket, Socket