ksh if with several conditions

Question

I'd like to know what's the syntax for this kind of if in ksh :

if [[ $tmpEngine != "a" || $tmpEngine != "b" || $tmpEngine != "s" ]]; then
   ...
fi

Actually, my code doesn't work, what's the problem here ? The problem is not about the meaning of my if, but rather how to write it correctly from a syntax point of view.

Solution

Whatever $tmpEngine value, this test is always true, I mean, $tmpEngine cannot be a, b and s at the same time so at least two of the comparisons are always true.

You probably want:

if [[ "$tmpEngine" != "a" && "$tmpEngine" != "b" && "$tmpEngine" != "s" ]]; then
   ...
fi

Comments

[user1058398]

You right, small mistake from my side but anyway, my code doesn't work because of a syntax problem.

[jlliagre]

Do you mean my answer doesn't address the problem described ?