I can't remove my app


Since one week using the mangoh green with legato 16.07, I didn’t have any problems, but today I was trying to work with the UART so I made a basic program who just do an echo of the UART read.

So first I installed my program and then I set my UART 1 to the IOT 0 breakout board by doing this AT command in /dev/ttyAT/:

Now in my program I opened the UART tty by using open("/dev/ttyHSL1") and it was not working. Then I tested both UART using microcom and a scope on the IOT board connected to the IOT1 and I deducted that the good tty was ttyHS0.

So, knowing this I wanted to change my code, and It doesn’t work… I tried to uninstalled it with Dev Studio and by command line but both stay stuck in those state :
DEV STUDIO: Payload copied: 11734/11734
CONSOLE: Removing app 'echoUART'... ^C***Error: Couldn't remove app 'echoUART'

Also there is something very weird, after I tried to remove the app and it doesn’t success, the system began to be very slow. E.g: When I’m doing a app status, there is 1s second between each lines.

Do you have any idea where I can find the logs for the command app ?
Hope you can help me understand the problem.


Hi, Reunan,

Very weird.

First, the logs are accessible on the target using the ‘logread’ command. This is a standard Busybox tool that prints the contents of the circular RAM buffer that Busybox’s syslogd is using to hold the logs.

If you can ssh into your board, you can also run ‘top’ to see what’s eating RAM/CPU. It sounds like you have a runaway process.

The update problem sounds like an issue we have fixed recently. You can try running 'config delete apps/echoUART" to clean out any configuration data related to that app. Then restart legato (“legato restart”), and see if you can install your new version of the app.


Thanks for your response.
I launched top while installing an app and randomly I have the updateDeamon processus stuck to 99%. But If I wait somthing like 5mn the installation success.
It’s really weird…

If you need any logs to try to understand I’ll provide them to you.