Green’s Dictionary of Slang

keen, desperate for.

1917		‘A-No. 1’ From Coast to Coast with Jack London 39: Fee-hungry as he was, he ran so close at our heels, that we escaped from his clutches only by a headlong dive from the car.
1940		R. Chandler Farewell, My Lovely (1949) 199: Them old cops get sap-hungry once in a while.