What is the full steps to use acme-client-portable with letsencrypt?

[silvioprog]

Hello,

I would like to see some document showing the full steps to use acme client with letsencrypt CA. This was my result (the info below are just fictitious, however I've tried it with real info in my production environment and got similar errors):

1. root@myvps:/home/myuser# mkdir /etc/ssl/acme
2. root@myvps:/home/myuser# mkdir /etc/ssl/acme/private /etc/acme
3. root@myvps:/home/myuser# chmod 0700 /etc/ssl/acme/private /etc/acme
4. root@myvps:/home/myuser# acme-client -vNn mydomain.org www.mydomain.org
5. acme-client: /var/empty: chroot: No such file or directory
6. root@myvps:/home/myuser# acme-client: acme-client: acme-client: acme-client: /var/empty: chroot: No such file or directory
7. /var/empty: chroot: No such file or directory
8. /var/empty: chroot: No such file or directory
9. /var/empty: chroot: No such file or directory
10. acme-client: tls_config_set_ca_file: failed to open CA file '/etc/ssl/cert.pem': No such file or directory: No such file or directory
11. acme-client: /var/empty: chroot: No such file or directory

If I've understood the log, do I need to create a /var/empty directory too?

I've used certbot and it have worked fine, but I'm don't like to download a lot of python packages just to use a letsencrypt client, so I'm trying acme client, however I'm not sure if it really uses letsencrypt REST API to automate the steps, and I don't know how I could do it manually. :-/

Edit 1:

I'm using nginx server 1.12.0 downloaded from its PPA.

Edit 2:

I'm using Ubuntu Sever 16.04 - 64 bits.

Edit 3:

The steps I've tried was from man acme-client.

[silvioprog]

I've fixed all errors above editing the files config.h and http.c to adapt it for my environment (ubuntu) and finally it works in part. I'm going to open a new issue with next errors I'm getting.