Posix SITL target - Can't see the filesystem, no ls or cd commands

Dear all

I have executed
make posix_sitl_default gazebo

PX4 shell and gazebo up and running, simulation seems to work.

However when I tried to take a look at the mixer files I realised that there was no ‘ls’, ‘cd’ or ‘cat’ commands.

I was expecting to have the same commands and see the same filesystem as when running directly on the pixhawk hardware.

Is this normal? what am I missing?


Can anyone shed some light here?
Why can’t we see a filesystem in posix_sitl_default implementations?


A more specific question might help.
If I want to enable logging of a particular topic https://dev.px4.io/advanced-logging.html suggests creating a file called logger_topics:

<topic_name>, <interval>```

How do I create this file in a posix target?

I’ll answer myself:

I found out that the shell in posix systems is not a real linux shell, but a very basic custom one.

The Nuttx based systems have a more complete shell that is a standard part of Nuttx.