From 2e6e5425d0ba0f44b8e47b4d792734eeac7adbe8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Petazzoni?= <jerome.petazzoni@gmail.com>
Date: Fri, 4 Feb 2022 08:30:54 +0100
Subject: [PATCH] =?UTF-8?q?=E2=9E=95=20Add=20platform=20check=20Dockerfile?=
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---
 slides/containers/Buildkit.md | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/slides/containers/Buildkit.md b/slides/containers/Buildkit.md
index 203e3d75..4684e51e 100644
--- a/slides/containers/Buildkit.md
+++ b/slides/containers/Buildkit.md
@@ -325,6 +325,29 @@ class: extra-details
 
 ---
 
+## Checking runtime capabilities
+
+Build and run the following Dockerfile:
+
+```dockerfile
+FROM --platform=linux/amd64 busybox AS amd64
+FROM --platform=linux/arm64 busybox AS arm64
+FROM --platform=linux/arm/v7 busybox AS arm32
+FROM --platform=linux/386 busybox AS ia32
+FROM alpine
+RUN apk add file
+WORKDIR /root
+COPY --from=amd64 /bin/busybox /root/amd64/busybox
+COPY --from=arm64 /bin/busybox /root/arm64/busybox
+COPY --from=arm32 /bin/busybox /root/arm32/busybox
+COPY --from=ia32 /bin/busybox /root/ia32/busybox
+CMD for A in *; do echo "$A => $($A/busybox uname -a)"; done
+```
+
+It will indicate which executables can be run on your engine.
+
+---
+
 ## More than builds
 
 - Buildkit is also used in other systems: