Maybe just touch a file somewhere in /tmp or /run or somewhere and do if [ -f $file ]; then touch $file ... If you never reboot could set up a cron job to dele

Maybe just touch a file somewhere in /tmp or /run or somewhere and do if [ -f $file ]; then touch $file ... If you never reboot could set up a cron job to delete it. Or store a counter in the file and output each time it reaches x % N. Might be susceptible to race conditions, so could wrap it in a flock or something...