x’00’

8

Literal “USER”

x’08’

8

Logonid of the requesting user

x’10’

8

Literal “BACKCHN”

x’18’

20

Up to 5 return addresses

x’2C’

8

Literal “ACB”

x’34’

a

The ACB for the failing request where “a” is

b

The length of the area obtained from the ACBLEN field(x’02’ offset into ACB)

x’18’+a

8

Literal “RPL”

x’20’+a

b

The RPL for the failing request where “b” is the length of the area obtained from the RPLLEN field (x’02’ offset into RPL)

x’28’+c

8

Literal “ACVALD”/ACALT”/”ACRULE”/”ACGRSRC”/”INVCTLB” (where “c” is value of “a”)

x’30’+c

d

Requesting control block identified by previous literal (where “d” is the length of the identified control block, except in the case of “INVCTLB” when the length is set to 256 bytes)

x’30’+e

8

Literal “END” (where “e” is the value of “c” + the value of “d”).