DLL Programmer's Guide for TNS/R Systems

Glossary
DLL Programmer’s Guide for TNS/R Systems—522203-002
Glossary-3
loadList: A list of all the libraries that must be loaded for a given loadfile to execute. A
loadfile's loadList includes all the libraries in the given loadfile's libList plus all the
libraries in those loadfiles' libLists, and so forth; it does not include the implicit
(system and millicode) libraries. The loadList order is the sequence in which these
loadfiles are to be loaded when they are not already loaded by a previous
operation. The loadList of the program includes all the loadfiles present in the
process, in the order they were loaded.
localized: The import-control characteristic of a loadfile that allows it to import symbols
only from the loadfile itself followed by the libraries in its libList, libraries that those
libraries re-export, and from these, any successions of re-exported libraries. See
also re-exported library and searchList.
millicode library:Low-level TNS/R library routines. Although separate from it, the
millicode can be considered an adjunct of the system library.
PIC (Position-Independent Code): Executable code that need not be modified to run at
different virtual addresses. External reference addresses appear only in a data
area that can be modified by the loader; they do not appear in PIC code.
preempt: When the linker’s binding of a symbolic reference to a symbol defined in the
same DLL is rebound by the loader to a definition in another loadfile.
process: An instance of the execution of a program.
program: A loadfile that can be invoked externally, e.g., by a RUN command. An
application comprises a program and zero or more libraries.
public library: A TNS/R hybrid SRL, which offers widely used functions, such as a
compiler run-time library and which is installed and controlled by a system
administrator. A loadfile must explicitly reference a public library in order to access
it.
public SRL: See public library.
re-exported library: A library whose symbols are made available by another DLL to
any localized client of that DLL. Re-export is an attribute of the DLL's libList entry
for that library. This attribute is specified by the DLL's programmer and recorded by
the linker as a DLL is built. It affects only localized clients of the DLL. This feature
allows a symbol to be moved from one DLL to another without relinking clients of
the original DLL.
Re-exporting is transitive; i.e., if A re-exports B and B re-exports C, then A re-
exports C. Thus, re-exported libraries can re-export other libraries to form a
succession of re-exported-library of arbitrary length.
reference: See symbolic reference.
searchList: For each loadfile, a list that specifies which libraries to examine, and in
which order, to locate symbol definitions needed by that loadfile. The linker and
loader construct the loadfile's searchList in accordance with that loadfile's import
control, which is set at link time. The system library and millicode (TNS/R) are