ASSIGN-TIME
The DISK parameter ASSIGN-TIME enables the operator to set default values for the time of allocation or for the release of a private disk and of a disk device with the appropriate updating of the system allocation log on the disk.
The allocation of the disk and the device on which the disk is mounted begins with ASS=*USER with the reservation of the disk by the user. At the same time the system ID is entered in the system allocation log. The disk and the device are released when the disk is released by the user, and the system allocation log is cleared.
If ASS=*OPERATOR is used, the disk and device on which it is mounted are allocated independently of the allocation by the user. If the disk is already online, the disk and the device are allocated immediately, otherwise allocation occurs after the activation interrupt but no later than at the time of an allocation request by the user. The disk and the device remain allocated until the operator returns the allocation by entering ASS=*USER and all users have released the disk.
Disks which are to be accessed by a system over an extended period, should be allocated via ASS=*OPERATOR. This avoids unnecessary allocation and release logs.
If a disk is allocated with ASS=*OPERATOR then it is important to ensure that the setting ASS=*USER is made before the device is detached using the command DETACH-DEVICE ...,FORCE=*NO since the DETACH-DEVICE command will otherwise be rejected. Only in this way can the allocation log be cleaned up correctly.
Allocation start
ASS=*USER with the first user request
ASS=*OPERATOR
with the activation interrupt when mounting (ATTACH-DEVICE)
immediately if the disk is already online
at the first allocation request by the user
Allocation release
ASS=*USER with last user release
ASS=*OPERATOR
with or after SET-DISK-PARAMETER ASSIGN-TIME=*USER
with or after SET-DISK-PARAMETER ASSIGN-TIME=*STD (and default value ASSIGN-TIME=*USER set)
if no task is still reserving the disk
OPERATOR-CONTROL
By means of this DISK parameter the operator specifies whether initial reservations of disks by tasks are to be checked. If the operator activates monitoring for a disk, the following message is displayed with each initial allocation of the disk:
NKA0004 ALLOCATION OF DISK '(&00)' IN USAGE MODE '(&01)' BY USER TASK
PERMITTED? REPLY (Y=ALLOCATION ACCEPTED; N=ALLOCATION REJECTED)
This message requests the operator to decide whether the specified disk of the requesting task is to be allocated in the allocation mode. Only in the case of a positive response to this message (TSN.Y) is the disk reserved by the task, otherwise this and all subsequent allocation attempts are rejected without any additional operator action.
If a disk for which the DISK parameter OPERATOR-CONTROL is set is already reserved by a job at this time, message NKA0004 is output for this disk only when it is released by the allocating job and is to be reallocated.