gtpg2m15General Macros

CREEC-Create a New ECB with Attached Core Blocks

This general macro creates an independent entry control block (ECB) for immediate or deferred processing. The ECB is created on the same I-stream, in the same subsystem, and subsystem user as the creating ECB.

A storage block on data level 0 and an optional variable-sized (0-104 bytes) parameter list are passed to the created ECB. The control program moves the specified core block reference word (CBRW) and the parameters into an interim block of available storage and adds the block to either the deferred processing list or the postinterrupt (ready) list. Operational Program Zero (OPZERO) initializes an ECB with the CBRW on data level 0, initializes the parameters in the work area, releases the interim block, and starts the specified program with an Enter with No Return (ENTNC).

Format




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

prog
The name of the program that is to be activated with the created ECB. The name must be four character starting with an alphabetic character (A through Z). This method generates a V-con which is resolved at link edit time into a Program Allocation Table (PAT) displacement. This is the preferred method for specifying the program name.

PROGRAM
The name of the program can be provided using the PROGRAM parameter.

Either the positional parameter 'prog' or the keyword parameter 'PROGRAM' is required. This method generates constant data which will be used at execution time to determine the Program Allocation Table (PAT) displacement. This method has a longer path length than the one described above.

prog
The name of the program that is to be activated with the created ECB.

(reg)
A register (R0-R7) that contains the address of the program name.

datalevel
The data level of the block to be passed to the created ECB. The valid values are D0 through DF.

When the new ECB is dispatched, the block from the data level of the issuing ECB will be available to the new ECB on its data level 0.

When control is returned to the issuing ECB, the storage block previously attached at the level is detached and is no longer available for use by the issuing ECB.

DECB=(reg)|label1
The label or general register (R1-R7) containing the address of the data event control block (DECB) that contains the block to be passed to the created ECB.

When the new ECB is dispatched, the block from the DECB of the issuing ECB will be available to the new ECB on data level 0.

When control is returned to the issuing ECB, the storage block previously attached at the DECB is detached and is no longer available for use by the issuing ECB.

R
Specifies that the created ECB is to be dispatched with a high priority. If you specify this parameter, the ECB is placed on the post interrupt (ready) list.

D
Specifies that the created ECB is to be dispatched with a low priority. If you specify this parameter, the ECB is placed on the deferred process list.

Entry Requirements

Return Conditions

Programming Considerations

Examples

None.