protected void close() throws IOException {
protected synchronized void close() throws IOException {
    protected void close() throws IOException {	if (native_fd != -1) {	    int close_fd = native_fd;	    this.native_fd = -1;	    VM_BootRecord bootRecord = VM_BootRecord.the_boot_record;	    int rc = VM.sysCall1(bootRecord.sysNetSocketCloseIP, close_fd);	}    }