bash script for calling crictl on the containerd unix socket; useful when running k3s in rootless mode

rootless_crictl.sh

#!/usr/bin/env bash

function main {
  set -eo pipefail

  local main_pid
  main_pid="$(systemctl show --property MainPID --user k3s-rootless | cut -d '=' -f2 | tr -d '\n')"

  local exe_pid
  for f in /proc/*/status; do
    local parent_pid
    parent_pid="$(grep PPid "${f}" | awk '{print $2}' | tr -d '\n')"
    if [[ "${main_pid}" -ne "${parent_pid}" ]]; then
      continue
    fi

    local child_process_name
    child_process_name="$(grep Name: "${f}" | awk '{print $2}' | tr -d '\n')"
    if ! [[ "${child_process_name}" =~ exe ]]; then
      continue
    fi

    exe_pid="$(grep -E '^Pid:' "${f}" | awk '{print $2}' | tr -d '\n')"
    break
  done

  k3s crictl --runtime-endpoint "unix:///proc/${exe_pid}/root/run/k3s/containerd/containerd.sock" "$@"
}

main "$@"

just to credit the source of inspiration: k3s-io/k3s#5786 (comment)