System Control Blocks

Offset
+0
+2
+3
+4
+0 4
+4 1
+5 • 3
Bytes and Field
Alignment Name
2 TCTUCBP
• • 1 TCTSCTR
• • • 1
4 TCTDCTR
TC'IOUTLM
TCTEXRLD
TCTTKRLD
TIMING CONTROL TABLE
Field Description, Contents, Meaning
TCT I/O Counter Table
The TCT I/O counter table consists of one DD entry
for each DD entry in the TIOT.
DD Entry
Each DD entry consists of the following 8 byte device
entry repeated for each UCB (device) associated with
a OD statement, and an 8 byte output limit extension.
Device Entry
Address of the UCB associated with this device.
Number of devices associated with this DD statement.
This number represents the number of Device entries
within this DD entry. This field contains zeros in
all but its first appearance in any DDentry.
Reserved.
340 OS System Control Blocks (Release 21.1)
Counter for EXCPs issued against this UCB.
OUtput Limit Extension
Maximum number, in binary, of EXCPs allowed on this
SYSOUT data set. Calculated from the OUTLIM
parameter on the user's SYSOUT DD statement and any
increases to that limit provided in the user exit
routine, IEFUSO.
A binary number of extents released by the DADSM
release routine. Collected only if RLSE was
specified in the SPACE parameter for this data set.
A binary number of tracks released by the DADSM
release routine. Collected only if RLSE was
specified in the SPACE parameter for this data set.
End of output Limit Extension
End of DD Entry