The type R node may contain Pascal instructions, functions and procedures, GLIDER common instructions and procedures, GLIDER functions, the GLIDER instructions PREEMPTION, RELEASE, STAY, If there is an instruction RELEASE (only one is allowed) it must be the first in the code. Its associated instruction may contain Pascal instructions, functions and procedures, GLIDER common instructions and procedures and GLIDER functions, the instructions SENDTO, DEASSEMBLE, EXTR, CREATE, and COPYMESS, and the procedures NOTFREE, BLOCK and DEBLOCK.