#!/bin/sh

DELAY="$1"  # if empty, run only once

while :; do
  # Don't log interrupts which have never fired
  # Suppress lines of the form
  #  12:    0    0    0    FOO_IRQ
  grep -ve "^ *[0-9]\+:[0 ]\+ [A-Za-z].*" </proc/interrupts

  if [ -n "$DELAY" ]; then
    sleep "$DELAY" || exit 1
  else
    break
  fi
done