5. OPERATION › 5.1 Operation Overview › 5.1.6 VCC User Exits › 5.1.6.3 File Systems User exit (VCCUSERX)

5.1.6.3 File Systems User exit (VCCUSERX)

The USS File Systems Collector provides an exit point when
records are to be written to the VCCDATA file or to SMF.  The
user exit may add site dependent data to the output record
and/or decide if the record should be written. VCC will
expect a return code to be placed in register 15 by the user
exit upon return.

An example of the VCCUSERX is provided in the library
sharedprefix.MICS.ASM as member VCCUSERX. The source provided
is in Assembler Language. You may copy VCCUSERX, modify it to
meet your specifications, assemble and link edit the object
deck as any name you choose. The name of the module is then
supplied to VCC via the USEREXIT keyword.

NOTE:  Saving the source code for your modified version of
VCCUSERX into sharedprefix.MICS.ASM as VCCUSERX is not
recommended as this member may be updated or replaced by
future maintenance, thus removing your modifications.  If you
have made modifications to the source code, copy your updated
member to sharedprefix.LOCALMOD.CNTL and document it.

For more details regarding linkage conventions, work areas,
and general purpose register usage, see the sample source
member provided in sharedprefix.MICS.ASM(VCCUSERX).

Use fields SBASOUSG (user segment offset), SBASOUSL (user
segment length), as the reference points for the user
segment.  You must place the user segment at the end of the
VCC record, and update the VCC record RDW (SBASRDW) with the
user segment length that is being added to the value that is
already in SBASRDW.  Make sure that fields SBASOUSG and
SBASOUSL are set properly when adding a user segment as
invalid results may cause VCC and/or VCA to fail.

Note that certain fields in the base segment are not
available to the user exit because they are filled in by VCC
later in its processing flow.  Therefore, do not attempt to
modify the following fields:

         SBASTYPE, SBASTIME, SBASDATE, SBASYSID, SBASLEN,
         SBASPSTR, SBASVID, SBASVERS.