Hacktastic script to print a PID from each mount namespace on a host

mnt_pids.rb

mntnses = Dir.glob("/proc/*/ns/mnt")

foundmnts = []
foundpids = []

mntnses.each do |mntns|
        actualmntns = `readlink "#{mntns}"`
        pid = mntns.split("/")[2]
        mntnum = actualmntns.gsub(/mnt:\[/, "").gsub(/\]/, "")
        #puts "#{pid} - #{mntnum}"

        if ! foundmnts.include? mntnum
                foundmnts << mntnum
                foundpids << pid
        end
end

puts foundpids