ZCPR3 utility which gives IMP v2.44 or v2.55 a shell escape 
capacity like the SHELL command in MEX+ for MS-DOS.  Adapted from 
MEX+2Z by Bruce Morgen and Jay Sage.  Library also contains 
ZOSIMP, a cosmetic patch to IMP which gives you a ZOS (Z 
Operating System) command in place of the CPM command.
                                   Fred Haines, 3 June 1987