TNS/E Native Application Conversion Guide

Introduction to Native Mode
TNS/E Native Application Conversion Guide—529659-003
1-15
Native Process Environment
Data Segments
When a process is created, several data segments are allocated for its use. This table
compares the data spaces for TNS and TNS/E processors:
:
The globals-heap segment in native processes is comparable to the user data segment
and the automatic extended data segment in TNS processes.
Process Type Data Segments
TNS process on
TNS/R processor
A user data segment, containing global data (for TAL, COBOL85, and
small memory-model C programs) and the user data stack for TNS
procedures
An automatic (compiler-generated) extended data segment,
containing extended global data and local data, and optionally a heap
(for C and C++ programs)
A main RISC stack segment, containing the stack for nonprivileged
native procedures
A privileged RISC stack segment, containing the stack for privileged
native procedures
A process file segment (PFS), used by the operating system
Optional program-allocated extended data segments (selectable or
flat segments)
TNS process on
TNS/E processor
A user data segment, containing global data (for TAL, COBOL85, and
small memory-model C programs) and the user data stack for TNS
procedures
An automatic (compiler-generated) extended data segment,
containing extended global data and local data, and optionally a heap
(for C and C++ programs)
A main memory stack for nonprivileged TNS/E native procedures.
A privileged memory stack for privileged procedures.
TNS/E native
process
A globals-heap segment, containing program global data and,
optionally, a heap
A main memory stack for nonprivileged TNS/E native procedures.
A privileged memory stack for privileged procedures.
A main register stack engine (RSE) backing store for nonprivileged
procedures
A privileged RSE backing store for privileged procedures
Zero or more DLL data segments
A process file segment (PFS), used by the operating system
Optional program-allocated extended data segments (selectable or
flat segments)