The time hounoured syntax for a for loop in a UNIX script is what you see below and that is what works with the default shell in Sun’s Solaris UNIX operating system, ksh88.
for i in 1 2 3 4 5 6 7 8 9 10
do
if [[ -d dir$i ]]
then
:
else
mkdir dir$i
fi
done
There is a much nicer syntax supported syntax the advent of ksh93. It follows C language conventions found in all sorts of places like Java, Perl, PHP and so on. Here is an example:
for (( i=1; i<11; i++ ))
do
if [[ -d dir$i ]]
then
:
else
mkdir dir$i
fi
done