(amd64)ubuntu@localhost:~$ snappy list -v
Name          Date       Version Developer  
ubuntu-core   2015-09-22 181     ubuntu*    
generic-amd64 2015-09-24 1.4     canonical* 
(amd64)ubuntu@localhost:~$ cat > cfg.yaml <<'EOF'
> config:
>   ubuntu-core:
>     network:
>       ppp:
>         - name: chap-secrets
>           content: mysecret
> EOF
(amd64)ubuntu@localhost:~$ sudo snappy config ubuntu-core cfg.yaml 
open /etc/ppp/chap-secrets: read-only file system
(amd64)ubuntu@localhost:~$