Log manager domain exit XLGSTRM
There is one exit point, XLGSTRM, in the log manager domain.
Youcan use XLGSTRM to modify a request to MVS to create a new log stream.
Youcan change the model log stream name and other parameters before they are
passed to the MVS system logger.
If a log stream connection request from CICS to the MVS system logger fails
because the log stream is not defined to MVS, CICS issues a request to the MVS
system logger to create the log stream dynamically, using a model log stream
definition.
The model log stream name that CICS passes to MVS depends on whether the
journal name refers to the system log or a CICS general log, as follows:
CICS system logs

sysname

.DFHLOG.MODEL—for example, MV10.DFHLOG.MODEL.
CICS general logs
LSN_qualifier_1.LSN_qualifier2.MODEL. The defaults for these two
qualifiers are the CICS region userid and the CICS region APPLID, but they
can be user-defined values specified in a JOURNALMODEL resource
definition.
For example, if the CICS region userid is CICSHT## and the APPLID is
CICSHTA1, the default model name is CICSHT##.CICSHTA1.MODEL.
The following information is passed to an XLGSTRM global user exit program:
vActual log stream name
vDefault model log stream name
vSystem log flag
vMVS system logger IXGINVNT parameter list.
The exit can amend the model stream name by updating UEPMLSN. Use the
IXGINVNT MF=M form which allows the exit to override other MVS system logger
options from the model log stream, allowing for even greater flexibility.
Here is an example of how your exit program can change the structure name:
L R9,UEPIXG
IXGINVNT REQUEST=DEFINE,
TYPE=LOGSTREAM,
STRUCTNAME=NEW_STRUCTURE,
MF=(M,(R9),NOCHECK)
...
NEW_STRUCTURE DC CL16'LOG_SYSTEST_009'
Here is an example of how your exit program can change the model stream name:
L R3,UEPMLSN R3 = address of stream name
MVC 0(26,R3),=CL26'NEW.MODEL.NAME'
Youdo not need to code the list and execute forms of the macro or include the
IXGCON or IXGANSAA macros in your exit—these are provided by the CICS code
which actually issues the DEFINE request.
For information about the IXGINVNT service, see the

OS/390 MVS Authorized

Assembler Services Reference ALE-DYN

manual.
log manager domain exit
Chapter1. Global user exit programs 149