Actually, IFF (if and only if) there are only the 2 variations presented in the OP, you could just use a

@arr=split(/ /,$test);

... and count the size of the array

$size=scalar(@arr);

if its 4, arr[2]is the OS, otherwise no OS was specified

In reply to Re^3: Reg Exp by chrism01
in thread Reg Exp by Anonymous Monk

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