File control EXEC interface API exits XFCREQ and XFCREQC
The XFCREQ exit allows you to intercept a file control application programming
interface (API) request before any action has been taken on it by file control. The
XFCREQC exit allows you to intercept a file control API request after file control has
completed its processing.
Note: For information about the XFCAREQ and XFCAREQC exits that are invoked
for file control SPI requests, see “File control EXEC interface SPI exits
XFCAREQ and XFCAREQC” on page83. The API commands affected are:
vREAD
vWRITE
vREWRITE
vDELETE
vUNLOCK
vSTARTBR
vREADNEXT
vREADPREV
vENDBR
vRESETBR.
The XFCREQ and XFCREQC exits can be written only in assembler language.
Using XFCREQ, you can:
vAnalyze the request, to determine its type, the keywords specified, and their
values.
vModify values specified by the request before the command is executed.
vSet return codes to specify that either:
CICS should continue with the (possibly modified) request.
CICS should bypass the request. (Note that if you set this return code, you
must also set up return codes for the EXEC interface block (EIB), as if you
had processed the request yourself.)
Using XFCREQC, you can:
vAnalyze the request, to determine its type, the keywords specified, and their
values.
vSet return codes for the EIB.
Both exits are passed nine parameters as follows:
vThe address of the command-level parameter structure
vThe address of a token (UEPFCTOK) used to pass 4 bytes of data from
XFCREQ to XFCREQC
vThe addresses of copies of four pieces of return code and resource information
from the EIB
vThe address of a token (UEPTSTOK) that is valid throughout the life of a task
vThe address of a recursion count field
vThe address of a 16-byte area that is used if the request has been function
shipped.
file control EXEC interface API exits
70 CICS TS for OS/390: CICS Customization Guide