TNS/R Native Application Migration Guide

Introduction to Native Mode
TNS/R Native Application Migration Guide—523745-001
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Native Process Environment
Process Organization
Executable code for a process is contained in the following objects:
•
The initial program of the process, called user code. This code is read from the
program file.
•
A system library containing system-related procedures. This includes operating
system code that is accessible by the process using system procedure calls.
•
Optionally, a user library containing code that can be shared among several
applications. This code is read from an object file containing the user-supplied
library.
•
Optionally, for native processes, one or more native shared run-time libraries
(SRLs). A native SRL functions similarly to an extension of the system library. HP
supplies public SRLs; you cannot create your own. For example, the C run-time
library is in a public SRL.
When a process is created, it occupies space in virtual memory. The following
paragraphs discuss the basic organization of a process in terms of code spaces, which
are associated with the objects in the preceding list, and data spaces.
Code Spaces
A process has distinct code spaces that contain executable code. For TNS processes
the code spaces are:
•
UC (user code)
•
UL (user library)
•
SC (system code)
•
SL (system library)
•
SCr (system code RISC)
•
SLr (system library RISC)
For native processes the code spaces are:
•
UCr (user code RISC)
•
SRL (shared run-time libraries, including the native user library)
•
SCr (system code RISC)
•
SLr (system library RISC)