Call legato app from sh; returning/echoing values

Legato Linux distribution (Yocto project)
1

Hi there,

this seems to be so simple, I must oversee something.

I want to echo some information from an app and call this app from the command line.
What I mean:
If I call “date” in my shell, I receive the current date and time because the application that’s called by “date” prints it to the command line
If I call “app start myApp”, I got… silence. printf and LE_INFO are redirected to a logfile, I receive no output at all.

How can I print the output of my application to the command line (preferably without any other overhead messages like “Starting Legato App blablabla”)?

My goal is to call my app using a cgi script and process the output of the app.

Thank you and best regards

Frank

2

You might have a look on the cm tool as it can print message to command line.

3

Thanks, that helped.

My issue was that my app was sandboxed. In this case you cannot call it from a script (at least didn’t work for me), unsandboxing helped; app will be found in /legato/systems/current/apps//read-only/bin. This can than be called from a script.

Don’t forget to call exit(EXIT_SUCCESS) to avoid error messages to flow into your command result.

Path to the CM script that you know from your command line: legato-af/apps/tools/scripts at master · legatoproject/legato-af · GitHub