Each of the ISPF exit routines is passed a parameter list that contains parameters common to all the installation-wide exits and parameters that are specific to the user exit. The parameters are in the order shown here, followed by exit-specific parameters in the order shown under the individual user exit description. The common parameters are:

exitid

A fullword binary number that identifies the numeric code for the user exit.

userid

An 8-character field that contains the TSO user ID (left-justified) of the current TSO session. If ISPF is running in batch and there is no TSO user ID, the DSN prefix (as set by the TSO PROFILE PREFIX command) is placed in the Userid field. If there is no DSN prefix, the Userid field contains the characters 'BATCH '.

screenid

An 8-character field that identifies the active ISPF logical screen. Because ISPF supports up to 32 logical screens, the possible values are 0 through 9 and A through W.

At initialization and termination exit points, 0 indicates no active logical screens.

These identifiers are left-justified and the field is padded with blanks.

ZENVIR

32 characters of environmental information that is provided by the ZENVIR ISPF system variable. This variable is described in z/OS ISPF Reference Summary.

datalen

A fullword binary number that identifies the length of the exit data area, in bytes.

dataptr

The fullword address of the data area ISPF acquires for the exit routine. If you do not provide a data area name on the ISPMEPT macro, this address, as well as the data length, is 0. Note that the data area is always on a doubleword boundary and data length is a multiple of eight.

Standard OS linkage conventions are followed. For example: Register 1 (which points to a list of addresses; each address points to a different parameter) is used to pass the parameter list to the exit program. For more information about linkage conventions, refer to z/OS MVS Programming: Assembler Services Guide.