Jamieson, Fausset and Brown on Job 30:3

3. solitary--literally, "hard as a rock"; so translate, rather, "dried up," emaciated with hunger. Job describes the rudest race of Bedouins of the desert [Umbreit].

fleeing--So the Septuagint. Better, as Syriac, Arabic, and Vulgate, "gnawers of the wilderness." What they gnaw follows in Job 30:4.

in former time--literally, the "yesternight of desolation and waste" (the most utter desolation; Eze 6:14); that is, those deserts frightful as night to man, and even there from time immemorial. I think both ideas are in the words darkness [Gesenius] and antiquity [Umbreit]. (Is 30:33, Margin).