gtps1m5nSystem Macros

TPINC-Special Tape Interface

Use this system macro to provide an interface to certain tape control program (CP) routines for entry control block (ECB)-controlled segments in the tape handling area. These routines allow the ECB routine to:


Required Authorizations
Key0 Restricted System Common Storage

X

Format




Notes:

  1. symbol1

  2. symbol2

label
A symbolic name can be assigned to the macro statement.

symbol1
An interface function must be specified as symbol1. The interface functions are:

RESTART
Restart I/O operations for the specified tape.

QUIESCE
Set appropriate tape status as specified by symbol2 and await completion of outstanding I/O operations for the specified tape.

PURGE
Purge all outstanding I/O requests for the specified tape to the postinterrupt routine specified by symbol2.

SWITCH
Initiate a tape switch from active to standby for a specified tape.

MOUNT
Initiate processing to mount an ALT tape on the specified device.

FINDALT
Locate an ALT tape for a tape switch when no standby is available.

ACTIVATE
Activate a specific ECB or all ECBs currently on the tape wait list.

GETBUF
Get the blocks required for the buffer of a blocked tape.

RELBUF
Release the blocks from the buffer of a blocked tape.

symbol2
A tape status must be specified as the second parameter when the QUIESCE function is specified as symbol1. A postinterrupt routine must be specified as the second parameter when the PURGE function is specified as symbol1.

The tape statuses for the QUIESCE function are:

OFFLINE
Mark the specified tape offline prior to quiescing the tape.

AUXQ
Mark the specified tape auxiliary queued prior to quiescing the tape. Auxiliary queued is a term that describes temporary suspension of normal tape I/O operations due to conditions unique to tape processing. For example, when an end-of-volume condition is detected for an output tape, special handling is required to write trailer records, rewind the tape, and initialize a new tape.

When a tape is auxiliary queued, normal I/O requests are queued but no I/O is performed. Tape handling routines can force processing, however, by requesting a bypass of this suspension. An I/O request of this type is said to be a bypass auxiliary queue request.

NORMAL
Do not alter the status of the specified tape prior to quiescing the tape.

The postinterrupt routines for the PURGE function are:

ERROR
Hardware error post-interrupt routine.

EOF
End-of-file post-interrupt routine.

The option available with the ACTIVATE function is:

ABORT
The specified ECB will be removed from the tape wait list and exited.

Entry Requirements

Return Conditions

Programming Considerations

Examples

None.