Background

   The OpenVMS LDAP API supports both 32- and 64-bit client
   applications. In order to allow this, separate entry points are
   provided in the library for those functions that are sensitive to
   pointer size.

   When a user module is compiled, the header file LDAP.H determines
   the pointer size in effect and uses the C preprocessor to map
   the function names into the appropriate library entry point. This
   mapping is transparent to the user application and is effected by
   setting the /POINTER_SIZE qualifier at compilation time.

   For LDAP API users, switching between different pointer sizes
   should need only a recompilation-no code changes are necessary.

   This means that programs using the specification for the C LDAP
   API, as described in the Internet Engineering Task Force (IETF)
   documentation, can be built on OpenVMS with either 32-bit or
   64-bit pointer size, without having to change the source code.