Loadfiles - HP eld Manual

Glossary
mapped to different addresses for different processes in the same CPU. PIC
introduces several new elements into ELF files, some of which are adapted from the
Intel LP64 ELF structure. TNS/E supports only PIC files. TNS/R supports PIC and non-
PIC file types.
Program. This term describes one type of loadfile that is capable of being run on the
system. This is the main program and there can only be one program associated with a
process.
Public Libraries. A set of libraries (offering widely-used functions) that are managed as part
of the system, available to all users of the system, and in large part supplied by HP,
although it is possible for customers and third parties to provide DLLs to be added to
the public DLLs. A loadfile must explicitly reference a public library in order to access it.
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.
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 libraries of arbitrary length.
Region. The Itanium® architecture divides the address space into eight regions, indexed
by the high-order three bits of the 64-bit address. TNS/E initially implements just two,
regions 0 and 7: region 0 is mapped per-process; region 7 is shared by all processes.
Sign extension places "negative" 32-bit addresses in region 7. Note that the high bit of
the 32-bit address on TNS/E determines global addressing, and privilege is an attribute
of the page; the MIPS architecture on TNS/R is just the opposite.
Relocation. the process of assigning load addresses to the different parts of a program,
adjusting the code and data in the program to reflect the assigned addresses.
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 are appended to every
searchList. A loadfile's searchList is unaffected by the import control of any other
loadfile.
Sections and Segments. The TNS/E object file is organized into contiguous items called
sections. There is an array of ELF section headers that contains the type and name of
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Glossary-5
Program