Infinite while loop

Infinite while loop:

while :
do
  echo "[CTRL+C] to break"
  sleep 1
done

One liner:

while :; do echo "[CTRL+C] to break"; sleep 1; done

With counter:

ii=0;
while :;
do
  ii=$(expr $ii + 1);
  echo "[CTRL+C] to break... ${ii}"
  sleep 1;
done;

Piping in text, one loop per line:

ls | while read -r LINE;
do
  echo $LINE;
done;

Note: When pipe is is used, a subshell is used so values in parent shell will not be affected from within the loop