gtpi1m5q | System Installation Support Reference |
The virtual reader exit, UELB, makes it possible to perform the following
operations on a virtual reader: OPEN, READ NEXT RECORD, CLOSE.
UELB is called by the common access device routine (CEL6), when the
ddname indicates the virtual reader.
Input
- R6
- Parameter list containing the following:
- Action code
- Spoolid
- Data level
- Saved data area.
Programming Considerations
- IBM provides sample assembler code for UELB. This sample code
supports a virtual reader for VM/ESA 1.1. Supporting a virtual
reader for any other release of VM can require you to change UELB. If
changes are made, the interface (input and output) must remain the
same.
- The data read must be put on the data level that is specified in the
input.
Return Values
R6 should contain one of the following return codes:
- 0
- The operation performed successfully.
- 1
- Error performing the operation.
- 2
- End of device.