How GQSCAN returns resource information
GQSCAN returns the information in the form of resource information
blocks (RIB) and resource information block extensions (RIBE), as
shown below. For the description of RIB and the RIBE, see z/OS
MVS Data Areas in the z/OS Internet library. 
In the RIB, the following fields contain information on RIBEs:
- RIBTRIBE contains the total number of RIBEs associated with this RIB
- RIBNRIBE contains the total number of RIBEs associated with this RIB that GQSCAN could fit into the area specified on the AREA parameter.
- RIBEDEVN contains a 4-digit EBCDIC device number for RESERVEs issued on the system. For RESERVEs issued on other systems, RIBEDEVN contains zero.
If the value in RIBNRIBE is less than the value in RIBTRIBE, you may need to specify a larger area with the AREA parameter.
The number of RIBs and RIBEs you receive for a particular resource depends on the size of the area you provide, and the scope and token values you specify on the GQSCAN macro.