Opens a TCP or UDP connection to a remote
host on a specific
port. By default, TCP is used; to connect
host must begin with the protocol
udp://. If specified,
timeout indicates the length of time in
seconds to wait before timing out.
If the connection is successful, a virtual file pointer is
returned, which can be used with
functions such as
fputs(). If the connection fails,
false is returned. If
message are supplied, they are set to the
error number and error string, respectively.