gtpi1m5j | System Installation Support Reference |
The user device user exit, UELC, allows you to access a user-defined input
device. UELC allows you to open the device, read the next 4KB record
from the device, or close the device
UELC is called by the common access device routine (CEL6), when the
ddname indicates a user-defined device.
Input
- Input device characteristics in C$IDSINQ (General Data Set Inquire Block)
- The following parameters from C$IDSUXT (User Exit Definitions)
- An action code (CEL6_OPEN, CEL6_READ_NEXT_RECORD or CEL6_CLOSE)
- Data level
- Pointer to saved common access data (structure defined in tpfio.h)
- User field in GDS inquiry block.
Programming Considerations
- UELC is shipped in skeleton form, with one return statement.
- All data levels must be returned to the caller in the same state they were
upon entry.
- The data read must be put on the data level that is specified in the
input.
Return Values
- CEL6_SUCCESS
- The operation performed successfully.
- CEL6_ERROR
- Error performing the operation.
- CEL6_END_OF_DEVICE
- End of device.