Add caller pid

[ghost]

The caller pid is not passed. Adding (self) to get the caller process id.

[oubiwann]

There is (or used to be) a source file somewhere ... but maybe we gave up on that approach for the old don’t recall, and have to look into it. If that has completely gone away, I’ll just approve this PR; if I do end up locatining it, I’ll tell you where the markdown is that needs to be changed.