Using the RUNCHAIN command (see RUNCHAIN, storage can be scanned
for a chain of linked control blocks. The RUNCHAIN command can be
invoked either by entering RUNCHAIN on any interactive report command
line, or by assigning RUNCHAIN to a PF key. When invoked, you are
shown a popup panel similar to the following: Figure 1. Sample Storage RUNCHAIN Command entry display
File View Services Help
┌───────────────────────── Storage RUNCHAIN Command ──────────────────────────┐
│ │
│ Enter the required fields and press Enter . │
│ │
│ Start Address . . . . . . . │
│ Max Number Control Blocks 9999 (Decimal) │
│ Forward Pointer Offset . . . (Hex) │
│ End of Chain Identifier . . (Hex, Default Values: All │
│ 0's and all F's) │
│ Eyecatcher Text . . . . . . │
│ Eyecatcher Offset . . . . . (Hex) │
│ │
│ │
│ F1=Help F3=Exit F12=Cancel │
└─────────────────────────────────────────────────────────────────────────────┘
000011 n/a 01 PARM1 PIC X(4) .
000012 n/a 01 PARM2.
Data Field Values:
PARM1 = 0001
PARM2 = HEADING FOR IDIXSNAP
F1=Help F3=Exit F5=RptFind F6=Actions F7=Up F8=Down
F10=Left F11=Right
The forward pointer at the Forward Pointer Offset is assumed to
be a 31-bit address.
The End of Chain Identifier is assumed to be a 32-bit hexadecimal
value. If less than 8 hexadecimal digits are specified, then the
specified value is padded with leading zeroes to form a 32-bit hexadecimal
value.
If a 64-bit Start Address is specified:
The forward pointer at the Forward Pointer Offset is assumed to
be a 64-bit address.
The End of Chain Identifier is assumed to be a 64-bit hexadecimal
value. If less than 16 hexadecimal digits are specified, then the
specified value is padded with leading zeroes to form a 64-bit hexadecimal
value.
For a given Start Address and Forward Pointer Offset, the RUNCHAIN
command follows the chain of control blocks until one of the following
end conditions is met:
The number of control blocks scanned has exceeded the maximum
number set by the user (the default value is 9999).
The forward pointer of the current control block contains one
of the 'End of Chain' values. These values are:
00000000 for a 31-bit Start Address or 0000000000000000
for a 64-bit Start Address.
FFFFFFFF for a 31-bit Start Address or FFFFFFFFFFFFFFFF
for a 64-bit Start Address.
The initial start address, implying the chain has looped
A user supplied End Of Chain Identifier:
The value specified is automatically padded with leading zeroes
to a length of 8 digits for a 31-bit Start Address or 16 digits for
a 64-bit Start Address. A 64-bit address might include an underscore
(see Start Address above for details).
If more than 8 digits are specified for a 31-bit Start Address,
then the value is left truncated to 8 digits.
If more than 16 digits are specified for a 64-bit Start Address,
and the address does not include an underscore, then the value is
left truncated to 16 digits.
The forward pointer of the current control block points to invalid
or unavailable storage.
For each control block, its address and the first 32 bytes of data
are shown.
Optionally, you can provide an eyecatcher and its offset in the
control block, in which case, for each control block, the text at
the specified offset is compared against the supplied text, and if
they do not match, then a warning message is issued.
As an example of the RUNCHAIN command, the Storage RUNCHAIN Command entry display might be
specified as follows:
File View Services Help
┌───────────────────────── Storage RUNCHAIN Command ──────────────────────────┐
│ │
│ Enter the required fields and press Enter . │
│ │
│ Start Address . . . . . . . 0005C000 │
│ Max Number Control Blocks 9999 (Decimal) │
│ Forward Pointer Offset . . . 1C (Hex) │
│ End of Chain Identifier . . (Hex, Default Values: All │
│ 0's and all F's) │
│ Eyecatcher Text . . . . . . DFHSMQPH │
│ Eyecatcher Offset . . . . . 2 (Hex) │
│ │
│ │
│ F1=Help F3=Exit F12=Cancel │
└─────────────────────────────────────────────────────────────────────────────┘
000011 n/a 01 PARM1 PIC X(4) .
000012 n/a 01 PARM2.
Data Field Values:
PARM1 = 0001
PARM2 = HEADING FOR IDIXSNAP
F1=Help F3=Exit F5=RptFind F6=Actions F7=Up F8=Down
F10=Left F11=Right
Pressing Enter, the following display is presented: