There can be multiple DBCHQEP addresses.
Each DBCHQEP address contains the address of a DBCHQEP
Each such area queries one piece of environmental information, such as the installation
id that is defined in the HSISPB.
When the query is successful (QEPRC contains zero), the area addressed by the QEPRAP
field contains the requested information, and the QEPRDLEN field contains the number
of bytes of the data returned. QEPRMLEN is set to zero, and any provided message area
is filled with spaces in the specified, or default, character set.
When the query is unsuccessful (QEPRC contains a CLIv2 return code), the area addressed
by the QEPRAP field is unchanged, and the QEPRDLEN field contains zero. If a message
area if provided, QEPRMLEN indicates the length in bytes of the message in the specified,
or default, character set. The contents of the area are the Query Environment Results
(QER) which is described as the DBCHQER area.
Upon completion, the return code will be the first or only DBCHQEP's QEPRC value.