IPDL is the "Inter-*-communication Protocol Definition Language", where "*" includes "process" and "thread". Firefox-source-docs on IPDL.
WARNING: These wiki articles are extremely old, so they may not be accurate.
The IPDL/Getting started guide intends to be somewhat verbose and gentle introduction to the IPDL.
The IPDL/Five minute example shows examples of what C++ code you need to implement to make IPDL "work." Before reading this, you should be somewhat familiar with the IPDL (or good at learning by example.)
The IPDL/Low level setup walks you through setting up the support infrastructure (processes, threads, and sockets) that IPDL needs to send messages. Few people should need to read this.
Another IPDL tutorial (MDN) that provides with some more information about IPDL protocols.
ON HOLD Proposal for fine-grained shmem access control
- IPDL/Unit test generation: use IPDL specifications to generate unit tests that "extensively" explore the protocol-level interaction of two (or more) actors. The unit tests are intended to check the C++ implementation(s) of the actor interfaces.