z/VM: CP Commands and Utilities Reference - z/VM - IBM

Registers at entry:
R1 address of parameter list
R13 address of 72 byte save area for caller’s registers
R14 return address
R15 entry point address of exit routine
Parameter list format:
x’0 ’ Parameter list length
x’2 ’ Flag byte
1... .... GTRACE records requested
.111 1111 Reserved
x’3 ’ Reserved
x’4 ’ Address of the trace record
x’8 ’ Address of an eight byte output area for
the TOD value supplied by the exit routine.
Registers at exit:
R0-R14 unchanged
R15 return code
0 = record selected
4 = no TOD value available
8 = record not selected
The merge and selection exit returns an 8-byte time stamp for the individual record
and indicates whether the record should be selected for further processing.
TRACERED selects either CP or guest trace entries by time. If the timestamp of a
guest record is not returned by the exit routine, the record cannot be selected by
time.
The GCS merge and selection exit should select only GTRACE records when
requested by TRACERED.
A return code 4 to TRACERED results in the record being skipped if the record is to
be merged with others. If TRACERED is not merging multiple input files and if the
records are not being selected by time, however, the record will be processed for
output.
A return code of 8 indicates that the record should not be selected.
A return code of zero will result in the record being selected and merged using the
TOD value.
TRACERED Formatting Exit
The TRACERED program supports user specified trace formatting exits for guest
trace records recorded in system data files using the FID option of the GCS
GTRACE macro and the TRSOURCE command (BLOCK mode).
TRACERED reads blocks of data from system trace or CMS files, separates the
individual records, and passes each to the formatting exit which is identified in the
block descriptor record.
Make sure that the CMS loader can access the TRACERED exit routine.
TRACERED
Formatting Exit Interface: When TRACERED processes a trace record in a
system trace file block, or a CMS trace file block, it passes it to the user-supplied
formatting exit if available:
Chapter 3. CP Utilities 1883