Prior to invoking this service, your exit routine must:
- Prepare a definition of the requested symbol in a block of storage
whose format is described by mapping macro BLSRESSY. Set all fields,
including reserved fields, except the ESSYRDX field.
Use
one of these methods to prepare a definition:
- Place blanks in field ESSYSYM within the buffer in which you compose
your definition. Pass that buffer to the get symbol service to initialize
the buffer.
- Invoke macro BLSRESSY in a CSECT to generate an initialized block
of storage. Copy that block into the buffer in which you compose
your definition.
For a literal, use the BLSRDATS area in the BLSRESSY
area to identify LITERAL(n), which is an address space that contains
the literal from which the new definition is to be derived. The address
field LAD and the fields in the BLSRDATS area indicate the part of
the literal to be included in the derived definition. Using the values
in the areas, the caller of the service can specify all or part of
the actual literal value.
- Use the get symbol service to retrieve a definition of another
block into the buffer in which you compose your definition. Check
that the fields you expect to use are unchanged as part of your definition.
- Change only those fields that are needed to define the symbol,
address space, address, and attributes that you wish to associate
with a block of storage.
z/OS MVS IPCS Customization
Copyright IBM Corporation 1990, 2014