Kernel primitives of the HXDP executive

This paper describes the kernel of an Executive being implemented for the Honeywell Experimental Distributed Processor (HXDP) -- a vehicle for research in distributed computers for real-time control. The kernel provides message transmission primitives for use by application programs or higher level executive functions. In the paper we describe the message transmission primitives provided by the kernel and the rationale for their selection based upon the objectives and constraints described in a companion paper.