To figure out the kernel version and build without booting it, e.g. to install matching device drivers during an automated image build in something like CustoPiZer, use something like this:
function version_and_build_for_kernelimg() { kernelimg=$1 # uncompressed kernel? output=$(strings $kernelimg | grep 'Linux version' || echo) if [ -z "$output" ]; then # compressed kernel, needs more work, see https://raspberrypi.stackexchange.com/a/108107 pos=$(LC_ALL=C grep -P -a -b -m 1 --only-matching '\x1f\x8b\x08' $kernelimg | cut -f 1 -d :) dd if=$kernelimg of=kernel.gz skip=$pos iflag=skip_bytes output=$(gzip --decompress --stdout kernel.gz | strings | grep 'Linux version' || echo) fi version=$(echo $output | awk '{print $3}' | tr -d '+') build=$(echo $output | awk -F"#" '{print $NF}' | awk '{print $1}') if [[ -n "$version" && -n "$build" ]]; then echo "Version: $kernel" echo "Build: $build" else echo echo "Cannot determine kernel version and build number for $kernelimg" fi } Note that this has only been tested with kernels on RaspberryPi OS images, YMMV.
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