From d7312385e0b16d92783b791f2a5304f91d992ba7 Mon Sep 17 00:00:00 2001
From: Jonas Karlman <jonas@kwiboo.se>
Date: Sat, 30 May 2020 10:18:09 +0000
Subject: [PATCH] tools/docker: update readme

---
 tools/docker/README.md | 30 ++++++++++++++++++++----------
 1 file changed, 20 insertions(+), 10 deletions(-)

diff --git a/tools/docker/README.md b/tools/docker/README.md
index 70582a2e14..0c45417eb3 100644
--- a/tools/docker/README.md
+++ b/tools/docker/README.md
@@ -1,17 +1,27 @@
 # Build container
 
-**Clone repo**
+**Build docker image**
 
-* `cd ~/`
-* `git clone https://github.com/LibreELEC/LibreELEC.tv.git LibreELEC`
+Use the following command to create a docker image and tag it with `libreelec`.
 
-**Build container**
+```
+docker build --pull -t libreelec tools/docker/focal
+```
 
-* `cd ~/LibreELEC`
-* `docker build --pull -t libreelec tools/docker/bionic`
+See https://docs.docker.com/engine/reference/commandline/build/ for details on `docker build` usage.
 
-**Build image inside container**
+**Build LibreELEC image inside a container**
 
-* `docker run -v ~/:/home/docker -h libreelec -it libreelec`
-* `cd ~/LibreELEC`
-* `make image`
+Use the following command to build LibreELEC images inside a new container based on the docker image tagged with `libreelec`.
+
+```
+docker run --rm -v `pwd`:/build -w /build -it libreelec make image
+```
+
+Use `--env`, `-e` or `--env-file` to pass environment variables used by the LibreELEC buildsystem.
+
+```
+docker run --rm -v `pwd`:/build -w /build -it -e PROJECT=RPi -e DEVICE=RPi4 -e ARCH=arm libreelec make image
+```
+
+See https://docs.docker.com/engine/reference/commandline/run/ for details on `docker run` usage.