Module pid_namespace 

The PID namespace an owner record names, and the rule for owners of another one. What: The PID namespace an owner record names, and the rule for judging an owner that lives in another one. Why: A PID means something only inside its PID namespace. A wrapper in a container that probes a host owner’s PID finds no process (or an unrelated one), so it would judge a live owner dead and recover or retire what the owner still holds (issues 1781 and 1784). A record therefore names its namespace, and an owner of another namespace is judged by the age of its record instead of by the PID.

In TS you’d write (pseudocode):

const sameNamespace = readlinkSync('/proc/self/ns/pid') === record.ownerPidNamespace;

Constants

FOREIGN_OWNER_PATIENCE

How long an owner of another PID namespace counts as alive, measured from when its record was written. A commit or a lock hold lasts seconds to minutes; a crashed foreign owner stops blocking after this long.

Functions

age_outlives_patience

What: Whether a record of this age has outlived the patience; exactly the patience still counts as alive. Why: The boundary is a fact of the rule, so it is separated from the clock to be checked exactly.

current_pid_namespace

What: The identity of this process’s PID namespace, such as pid:[4026531836], or nothing where the system has none. Why: The kernel names a namespace by an inode; two processes share a PID space exactly when the names are equal.

foreign_owner_standing

What: Whether an owner recorded in recorded counts as alive without any PID probe, or nothing when the PID decides. Why: Callers share one rule: an owner of another namespace is alive until its record outlives the patience.

foreign_record_has_expired

What: Whether a record written by an owner of another namespace is old enough to stop counting as alive. Why: The record file’s modification time stands for when the owner started; a record that cannot be measured keeps its owner alive, because the wrapper never retires what it cannot prove dead.

is_other_namespace

What: Whether a recorded namespace and the reader’s namespace are both known and differ. Why: Without both names nothing proves the PID space differs, so the PID probe keeps its old meaning; a record written before this field existed carries no name.