Native Object File Structure; Code And Data Segments; Table 8-1. Loadfile Segments And Sections - HP nld Manual

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Native Object File Structure

nld and noft operate on native object files. A native object file has four main
components:
Headers of the following types, which contain information about the structure and
components of the object file:
File
Program
Section

Code and Data Segments

MDEBUG Section
TANDEM_GINFO section, which contains information used by the operating
system to load loadfiles (for example, a lists of unresolved references and
procedure information for creating run-time stack traces)
Code and Data Segments
The code segments of an object file contain the code for procedures and
subprocedures. In relinkable object files, resident and nonresident procedures are
intermixed in the file. In loadfiles, resident and nonresident procedures are in separate
code segments.
The data segments of an object file contain information, such as global variables in
pTAL and extern and static variables in C, that does not appear and disappear
with each invocation of a procedure or subprocedure. The compilers generate code
that uses the run-time stack to manage data that does appear and disappear.
Code and data segments are divided into sections. nld operates on sections for
linking, whereas the operating system operates on segments for loading programs into
virtual memory. The following table lists the sections within each segment:

Table 8-1. Loadfile Segments and Sections

Segments
Code
Data
on page 8-1
on page 8-2
Sections
Nonresident Text
Resident Text
Read-only Data
Large Initialized Data
Small Initialized Data
Small Uninitialized Data
Large Uninitialized Data
nld and noft Manual—520384-003
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