LU Index Dissection

This page is a part of the "Understanding IRIS" collection.  Many thanks to David Takle, for figuring this out, and sharing this with us:

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using David's Disassembly program, here is the anatomy of an LU Index:

; this is what normal index looks like
; each entry is 010 words long  (here 010 is octal for 8 in decimal)
; words 0-6 are the name ( if shorter, fill with 0's )
; word 7 is the Header block addr

001400: 153256  V.  ADDOR# 2,2,SEZ
001401: 141720  CP  INCZS 2,0
001402: 127264  .4  ADDCR 1,1,SZR
001403: 130267  07  COMCR 1,2,SBN
001404: 130662  12  NEGCR 1,2,SZC
001405:      0  ..  JMP 0
001406:      0  ..  JMP 0
001407:  23250  &(  LDA 0,@-130,2

001410: 152724  UT  SUBZS 2,2,SZR
001411: 127303  .C  ADDS 1,1,SNC
001412: 147715  OM  ANDS# 2,1,SNR
001413: 146400  M.  SUB 2,1
001414:      0  ..  JMP 0
001415:      0  ..  JMP 0
001416:      0  ..  JMP 0
001417:  23272  &:  LDA 0,@-106,2

001420: 153256  V.  ADDOR# 2,2,SEZ
001421: 144322  HR  COMZS 2,1,SZC
001422: 127263  .3  ADDCR 1,1,SNC
001423: 130661  11  NEGCR 1,2,SKP
001424: 130262  02  COMCR 1,2,SZC
001425:      0  ..  JMP 0
001426:      0  ..  JMP 0
001427:  23304  &D  LDA 0,@-74,2

001430:      0  ..  JMP 0
001431: 141720  CP  INCZS 2,0
001432: 127264  .4  ADDCR 1,1,SZR
001433: 130261  01  COMCR 1,2,SKP
001434: 131267  27  MOVCR 1,2,SBN
001435:      0  ..  JMP 0
001436:      0  ..  JMP 0
001437:  15263  .3  DSZ -115,2

                    ^^^^^^^^ ignore this part (just comes with my conv program)
                ^^ ascii equiv
         ^^^^^ octal value
^^^^^^ relative to start of index file

This page is a part of the "Understanding IRIS" collection.