What is POSIX PSE51 that Adaptive AUTOSAR based on?

Question

What is POSIX PSE51 that Adaptive AUTOSAR based on?

While studying Adaptive AUTOSAR, I found 'Adaptive AUTOSAR is based on POSIX PSE51'.

However, I cloudn't understand what is POSIX PSE51.

Someone can answer this question?

I want to know following...

• Where can I read the paper of POSIX PSE51?
• What is API supported in POSIX PSE51?
• Adaptive AUTOSAR will become like Linux? File System, System Call and so on.

Answer 1

The POSIX standard exists in different profiles, one of which is PSE51. It's a subset of the full POSIX profile, not requiring multiple processes (or threads), and not requiring file systems. PSE51 is the smallest subset, "Minimal real-time system profile" and is often used for the purpose that name indicates.

In addition to the usual POSIX specification, you can refer to the API Standards for Open Systems paper for the description of the various POSIX profiles. The paper has a "feature matrix" appendix, showing which APIs are included.

Adaptive AUTOSAR will become like Linux? File System, System Call and so on.

Adaptive AUTOSAR is POSIX-based, so it's like Linux in that broad sense. File systems are not part of PSE51. System calls are an implementation detail as far as POSIX is concerned, but using Linux as an example, many of its system calls are there for POSIX-specified functionality, so the same can conceivably be the case in Adaptive AUTOSAR.

Vendors are of course free to extend their implementations of Adaptive AUTOSAR beyond what the specification requires, so there could be vendor-specific multiprocessing or file system solutions.

In more practical terms, the relationship between Linux and adaptive AUTOSAR will likely be that adaptive AUTOSAR will be running within the context of Linux, for example, within a Docker container or such.

Answer 2

PSE51 is a subset of POSIX created for the purpose of embedded real-time systems. A description can be found in IEEE 1003.13-2003.

On the AUTOSAR adaptive platform, the subset applies for the application layer. Platform modules (which roughly correspond to the BSW modules on the AUTOSAR classic platform) are free to extend their API usage beyond the limitations of PSE51 if needed.

The AUTOSAR adaptive platform is not going to become like Linux, but Linux (or other POSIX-compliant OS) can be taken to host an AUTOSAR adaptive platform.