Description
Tells the server socket to accept a connection and return a new connected socket.
Returns
A list of up to four items. The first is a quoted string that echoes the command ("accept"). The second is a quoted string, either "ok" or an error. The third is a quoted string that specifies the name of the machine that just connected. The fourth is a reference to the socket that you can send more messages.
Optional Arguments
callback
Specifies the name of a function to receive the data.
timeout
If you use a callback, timeout specifies how long the function should wait for an answer. For a server socket, 0 is an acceptable value because a server should not shut down because no one has connected to it recently.
Description
Associates a port on the local machine with the socket.
Returns
A list of two quoted strings. The first string is the command name (“bind”) and the second is “ok” if successful or an error.
Required Arguments
localhost
Specifies the quoted local machine. You cannot bind to another machine.
port
Specifies the port that should be used.
Description
Closes a socket.
Returns
A list of two quoted strings. The first string is the command name (“close”) and the second is “ok” if successful.
Description
Connects to a listening socket.
Returns
A list of two quoted strings. The first string is the command name (“connect”) and the second is “ok” for a successful connection or an error sent back by the other socket.
Arguments
socketname
Specifies the name of the other socket. If you are connecting to a web server, this is the web address (the name is preferred to the IP address).
port
Specifies the port of the other socket to connect through.
Description
Retrieves the address and port of the socket at the other end of the connection.
Returns
A list of four quoted strings. The first echoes the command ("getpeername"). The second is either “ok” or an error. The third and fourth are the address and the port.
Description
Retrieves the address and port of the socket at this end of the connection.
Returns
A list of four quoted strings. The first echoes the command ("getsockname"). The second is either “ok” or an error. The third and fourth are the address and the port.
Description
Controls the socket’s blocking behavior.
Returns
A list of two quoted strings. The first string is the command name (“ioctl”) and the second is “ok” if successful or an error.
Arguments
FIONBIO, 1
FIONBIO means Non-Blocking I/O. If true, turns on the behavior and the argument.
Description
Tells the server socket to listen for connections.
Returns
A list of two quoted strings. The first echoes the command ("listen") and the second is "ok" or an error message.
Description
Receives either a stream message (recv) or a datagram message (recvfrom) from the other socket. If the two optional arguments are used, the data is not received immediately. Instead, the data is received when the function callback is called.
Returns
A list of three quoted strings. The first string is the command name (“recv” or “recvto”). The second is “ok” if successful or an error message if not. The third string is the data that was received. If a callback function is used, a fourth element is the socket that was used in the original recv or recvfrom message.
Required Argument
n
Specifies the number of bytes to receive from the other socket.
Optional Arguments
callback
Specifies the name of a function to receive the data.
timeout
If you use a callback, timeout specifies how long the function should wait for an answer.
Description
Sends the data in the argument to the other socket. Send sends a stream and sendto sends a datagram.
Returns
A list of three quoted strings. The first string is the command name (“send” or “sendto”). The second is “ok” if successful or an error message if not. The third string is any portion of the stream that could not be sent, or empty if all the data was sent correctly.
Arguments
stream
Specifies the command to send to the other socket.
dgram
Specifies the command to send to the other socket.
Notes
Either argument might need to contain binary data. JMP represents non-printable ASCII characters with a tilde (~) followed by the hexadecimal number. For example,
skt<<send(("GET / HTTP/1.0~0d~0a~0d~0a");
sends a “get request” to an HTTP server.