Source code in the unix programming language

#!/bin/sh
# Using a while control construct to emulate a for loop

l="1"                   # Set the counters to one
while [ "$l" -le 5 ]    # Loop while the counter is less than five
  do
  m="1"
  while [ "$m" -le "$l" ]  # Loop while the counter is less than five
    do
    printf "*"
    m=`expr "$m" + 1`   # Increment the inner counter
  done
  echo
  l=`expr "$l" + 1`   # Increment the outer counter
done

for i in `jot 5`; do
	for j in `jot $i`; do
		printf \*
	done
	echo
done

for (( x=1; $x<=5; x=$x+1 )); do 
  for (( y=1; y<=$x; y=$y+1 )); do 
    echo -n '*'
  done
  echo ""
done

foreach i (`jot 5`)
	foreach j (`jot $i`)
		echo -n \*
	end
	echo ""
end

for ((x = 1; x <= 5; x += 1))
do
	for ((y = 0; y < x; y += 1))
	do
		print -n '*'
	done
	print
done