# Detecting the platform when running a Docker based build

Common advice is to use uname -m or arch commands which should report something like x86_64 or i686 for 64 or 32-bit flavours of Linux running on Intel-esque systems. This works fine when running on a real machine, but all falls apart when querying on 32 bit docker image running on a 64-bit host, since these commands query the underlying operating system kernel rather than the platform of the container.

A workaround is to look at the system’s binaries. The Elf format header specifies that the fourth byte of the header will either be 01 or 02 for a 32 or 64-bit system, so we can look at an assumed-available binary (such as /bin/bash) and pull out the relevant information.

Imported using <script> tag

Using plugin:

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