TCPIPV6NetworkStream

TCPIPV6UNIXNetworkStream Class

The TCPIPV6NetworkStream class manages TCPIP version 6 stream objects. The class is a superclass of the TCPIPV6NetworkStreamReader and TCPIPV6NetworkStreamWriter classes, and the methods and instance variables that are defined by this class are common to both client and server programs.

Here is an example of simple IPv6 reader program.

int main () {
  SystemErrnoException new ex;
  TCPIPV6NetworkStreamReader new server, connection;
  String new data;

  server openOn;
  if (ex pending) {
    ex handle;
  }

  connection = server acceptSock;
  if (ex pending) {
    ex handle;
  }
  data = server readText connection;
  printf ("%s\n", data);

  server closeSock;
}

And here is a simple program that writes a message to a TCPIP v6 connection.

static char *msg = "First connect.\n";

#include <ctalk/ctalkdefs.h>

int main (int argc, char **argv) {
  SystemErrnoException new ex;
  TCPIPV6NetworkStreamWriter new client;

  if (argc != 2) {
    printf ("Usage: ip6writer <server_hostname>\n");
  }

  client openOn argv[1];
  if (ex pending) {
    ex handle;
  }

  client writeText msg;
  
  client closeSock;
}

Instance Variables

sock

An Integer that contains the system-assigned file handle number of TCPIPV6NetworkStreamReader and TCPIPV6NetworkStreamWriter objects.

Instance Methods

addrInfo (String hostname, String canonnameout, List addrsOut)

Performs a lookup of hostname’s IPv6 addresses. If the lookup is successful, returns the host’s canonical name in canonnameout and each of the host’s addresses as a string in addrsOut. The method’s return value is an Integer with the number of addresses found.

If the lookup causes an error, the method raises an Exception (not a SystemErrnoException) and returns 0.

closeSock (void)

closeSock (Integer sockNum)

With no arguments, closes the receiver’s socket. If a socket file handle number is given as the argument, closes that socket. If closing the socket causes an error, the method raises a SystemErrnoException.

createSocketBasic

Creates a new IPv6 socket and sets the receiver’s sock instance variable, an Integer, to the system-assigned file number, and returns the sock instance variable. If an error occurs while creating a socket, the method raises a SystemErrnoException and returns 0.

readText (void)

readText (Integer sock_fn)

Read text from a network connection. With no arguments, the value of the receiver’s sock instance variable provides the socket file handle. If one argument is given, the argument, an Integer, provides the file handle number.

These methods return a String with the contents of the received message. If an error occurs while reading, the methods raise a SystemErrnoException and return NULL.

readVec (Integer sock_fn, Vector resultVec)

Reads binary data from the socket handle sock_fn into resultVec, and returns resultVec. The method raises a SystemErrnoException if an error occurs.

writeText (String textArg)

Writes the String given as the argument to the receiver’s socket. If the number of bytes written does not match the length of textArg, the method raises a SystemErrnoException.

writeVec (Vector dataVec)

Writes the contents of DATAVEC to the receiver’s socket. If the number of bytes written does not match the length of the data, the method raises a SystemErrnoException.