Future versions of sendmail might be able to use shared libraries. When they do, it will be possible to tune their specifications with the build-time macros shown in Table 2-10.
Table 2-10. Shared library build-time macros
Macro
Description
confSHAREDLIB_EXT
The shared library extension ( generally .so )
confSHAREDLIB_SUFFIX
The suffix that shows the version of the shared library
confSHAREDLIBDIR
The directory into which to install shared libraries