[MRTCAL\]VARIABLE /INDEX
Populate the MDX%HEAD% Sic structure with all the current index sec-
tions. Components are:
- MDX%HEAD%KEY
- MDX%HEAD%PRI
- MDX%HEAD%SCI
- MDX%HEAD%POI
Each individual component is appended a "number of entries" (i.e. size
MFOUND) trailing dimension compared to the MHEAD% equivalent structure
for one entry.