Overview

When you create a multi-threaded application you need to consider how each program in the application should operate: as a standard COBOL program, as a serial program, or as a reentrant program. Of the three types of program, programs compiled as REENTRANT(1) programs need most attention.

You also to need to consider how to:

Initialize applications
Manipulate threads
Create thread-local data

You should also be aware of common problems with multi-threaded programming.

Important: It is unsafe to modify or add environment variables in a threaded application on Linux systems. This is due to limitations of the underlying system libraries. It is however safe to read values from environment variables.