Question

Here is my statements:

print "Ss $# $2" >&3
if [ $# -eq 4 || $# -eq 3 ] && [ $2 != "d" ]
then
        print "sss"
else
        print "lol"
fi

The output is:

Ss 4 s
lol

Why is “sss” not being displayed?

Answer 1

Your if-condition isn’t syntactically correct. You can’t have || inside the brackets. Change it to use -o instead:

if [ $# -eq 4 -o $# -eq 3 ] && [ $2 != "d" ]
then
        print "sss"
else
        print "lol"
fi

Or, even better, use [[ (if your shell supports it) which is safer and has more features. It supports ||:

if [[ ( $# -eq 4 || $# -eq 3 ) && $2 != "d" ]]
then
        print "sss"
else
        print "lol"
fi