Common communication areas for IFI calls

The following communication areas are used on all IFI calls.

Instrumentation facility communications area (IFCA)
A monitor program's instrumentation facility communication area (IFCA) is a communications area between the monitor program and IFI. The IFCA contains information about the success of the call in its return code and reason code fields. The IFCA is a required parameter on all IFI requests.
Return area
You must specify a return area on all READA, READS, and command requests.
IFCID area
You must specify the IFCID area on READS and WRITE requests.
Output area
The output area is used on command and WRITE requests

Parent topic: Programming for the instrumentation facility interface (IFI)