Tcl_ChannelType *Tls_ChannelType(void) {
    unsigned int size;

    /*
     * Initialize the channel type if necessary
     */
    if (tlsChannelType == NULL) {

	/* Allocate new channel type structure */

	size = sizeof(Tcl_ChannelType) * 2; /* Base size plus pad for future changes */

	tlsChannelType = (Tcl_ChannelType *) ckalloc(size);
	memset((void *) tlsChannelType, 0, size);

	/* Init structure */
	tlsChannelType->typeName	= "tls";
#ifdef TCL_CHANNEL_VERSION_5
	tlsChannelType->version		= TCL_CHANNEL_VERSION_5;
	tlsChannelType->closeProc	= TlsCloseProc;
	tlsChannelType->inputProc	= TlsInputProc;
	tlsChannelType->outputProc	= TlsOutputProc;
	tlsChannelType->seekProc	= NULL;