Keep Last Access Date following Read Access to a File (KLA)

The system administrator can prevent or control access to sensitive files by means of their own routines using the Open/Close Exit.

An example is to use the CLose Exit to reset the Last Access Date to the original value following a read access operation on a file (Display/ ONXFIND/User Option FIND).

(KLA) The Keep Last Access Mode is activated with the (KLA) command, and deactivated with the (KLA)OFF command.

Calling Conventions and Parameter Lists

The addresses of the Open/Close Exits should be entered in the YOPENAD/YCLOSEAD fields of the Global area (DSECT GLOBAL macro) (e.g. using CFSMAIN).

The Open and Close Exits will be called by CFS before and after processing the OPEN/CLOSE DVS macro call.

Register assignment / Parameters:

R1 Opcode.

X'00000001': Exit Call before executing the DVS macro.

Close Exit: Register R0 will contain the address of the FCB still open.

X'00000002': Exit Call after executing the DVS macro.

Open Exit: Register R0 will contain the adress of the opened FCB.

R13 Address of an 18 word Save Area.

R14 Return address in CFS.

R15 Start address: Start of the Exit.

Return information:

Return information in Register 15 will be evaluated following the return from an Open Exit with Opcode X'00000001'.

R15 = X'00000000': DVS Open Call may be executed.

R15 > X'00000000': DVS Open Call may not be executed.