In this article, we continue last week’s
discussion of PID namespaces (and extend our ongoing series on namespaces). One use of
PID namespaces is to implement a package of processes (a container) that
behaves like a self-contained Linux system. A key part of a traditional
system—and likewise a PID namespace container—is the
init process. Thus, we’ll look at the special role of the
init process and note one or two areas where it differs from the
traditional init process. In addition, we’ll look at some other
details of the namespaces API as it applies to PID namespaces.