accept

/*
 * call-seq:
 *      socket.accept => [ socket, string ]
 * 
 * Accepts an incoming connection returning an array containing a new
 * Socket object and a string holding the +struct+ sockaddr information about 
 * the caller.
 * 
 * === Example
 *      # In one script, start this first
 *      require 'socket'
 *      include Socket::Constants
 *      socket = Socket.new( AF_INET, SOCK_STREAM, 0 )
 *      sockaddr = Socket.pack_sockaddr_in( 2200, 'localhost' )
 *      socket.bind( sockaddr )
 *      socket.listen( 5 )
 *      client, client_sockaddr = socket.accept
 *      puts "The client said, '#{client.readline.chomp}'"
 *      client.puts "Hello from script one!"
 *      socket.close
 * 
 *      # In another script, start this second
 *      require 'socket'
 *      include Socket::Constants
 *      socket = Socket.new( AF_INET, SOCK_STREAM, 0 )
 *      sockaddr = Socket.pack_sockaddr_in( 2200, 'localhost' )
 *      socket.connect( sockaddr )
 *      socket.puts "Hello from script 2." 
 *      puts "The server said, '#{socket.readline.chomp}'"
 *      socket.close 
 * 
 * === Unix-based Exceptions
 * On unix-based based systems the following system exceptions may be raised if the
 * call to _accept_ fails:
 * * Errno::EAGAIN - O_NONBLOCK is set for the +socket+ file descriptor and no 
 *   connections are parent to be accepted
 * * Errno::EWOULDBLOCK - same as Errno::EAGAIN
 * * Errno::EBADF - the +socket+ is not a valid file descriptor
 * * Errno::ECONNABORTED - a connection has been aborted
 * * Errno::EFAULT - the socket's internal address or address length parameter 
 *   cannot be access or written
 * * Errno::EINTR - the _accept_ method was interrupted by a signal that was 
 *   caught before a valid connection arrived
 * * Errno::EINVAL - the +socket+ is not accepting connections
 * * Errno::EMFILE - OPEN_MAX file descriptors are currently open in the calling 
 *   process
 * * Errno::ENOBUFS - no buffer space is available
 * * Errno::ENOMEM - there was insufficient memory available to complete the
 *   operation
 * * Errno::ENOSR - there was insufficient STREAMS resources available to 
 *   complete the operation
 * * Errno::ENFILE - the maximum number of file descriptors in the system are 
 *   already open
 * * Errno::ENOTSOCK - the +socket+ does not refer to a socket
 * * Errno::EOPNOTSUPP - the socket type for the calling +socket+ does not 
 *   support accept connections
 * * Errno::EPROTO - a protocol error has occurred
 * 
 * === Windows Exceptions
 * On Windows systems the following system exceptions may be raised if 
 * the call to _accept_ fails:
 * * Errno::ECONNRESET - an incoming connection was indicated, but was 
 *   terminated by the remote peer prior to accepting the connection
 * * Errno::EFAULT - the socket's internal address or address length parameter
 *   is too small or is not a valid part of the user space address
 * * Errno::EINVAL - the _listen_ method was not invoked prior to calling _accept_
 * * Errno::EINPROGRESS - a blocking Windows Sockets 1.1 call is in progress or
 *   the service provider is still processing a callback function
 * * Errno::EMFILE - the queue is not empty, upong etry to _accept_ and there are
 *   no socket descriptors available
 * * Errno::ENETDOWN - the network is down
 * * Errno::ENOBUFS - no buffer space is available
 * * Errno::ENOTSOCK - +socket+ is not a socket
 * * Errno::EOPNOTSUPP - +socket+ is not a type that supports connection-oriented
 *   service.
 * * Errno::EWOULDBLOCK - +socket+ is marked as nonblocking and no connections are
 *   present to be accepted
 * 
 * === See
 * * accept manual pages on unix-based systems
 * * accept function in Microsoft's Winsock functions reference
 */
static VALUE
sock_accept(sock)
    VALUE sock;
{
    rb_io_t *fptr;
    VALUE sock2;
    char buf[1024];
    socklen_t len = sizeof buf;

    GetOpenFile(sock, fptr);
    sock2 = s_accept(rb_cSocket,fileno(fptr->f),(struct sockaddr*)buf,&len);

    return rb_assoc_new(sock2, rb_str_new(buf, len));
}