82 	byte	*Tail;		/* first free position			*/  member
99 	Q->Base = Q->Head = Q->Tail = Buffer;  in queueInit()
117 	if (Q->Tail == Q->Head) {  in queueAllocMsg()
124 	if (Q->Tail > Q->Head) {  in queueAllocMsg()
125 		if (Q->Tail + need <= Q->High) goto alloc; /* append */  in queueAllocMsg()
130 		Q->Wrap = Q->Tail;  in queueAllocMsg()
131 		Q->Tail = Q->Base;  in queueAllocMsg()
135 	if (Q->Tail + need > Q->Head) {  in queueAllocMsg()
140 	Msg = (MSG_HEAD *)Q->Tail;  in queueAllocMsg()
144 	Q->Tail	 += need;  in queueAllocMsg()
165 	} else if (Q->Head >= Q->Tail) {  in queueFreeMsg()
166 		Q->Head = Q->Tail = Q->Base;  in queueFreeMsg()
177 	if (((byte *)Msg == Q->Tail && !Q->Wrap) ||  in queuePeekMsg()