Starting VLF

Issue the following command to start VLF:

START VLF,SUB=MSTR,NN=xx

The two alphanumeric characters (xx) are added to COFVLF to form the name of the COFVLFxx member. If you do not code NN=xx, the system defaults to COFVLF00.

Note that VLF will not start unless SUB=MSTR is specified on the START command. SUB=MSTR means that VLF can continue to run across a JES restart. It is recommended that you arrange for the VLF start command to be issued automatically during the IPL process. If VLF is stopped and restarted during the life of an MVS™ IPL, any request by an application to retrieve or create a VLF object with a user token obtained prior to the restart causes VLF to pass a return code of X'10' back to the application and continue processing. The application should detect the return code and obtain a new token. For more information about using VLF macros, see z/OS MVS Programming: Authorized Assembler Services Guide.

COFVLFxx parmlib members can be concatenated. When they are concatenated, a class definition can span parmlib members.