Green’s Dictionary of Slang

scarf n.

(US) food, thus eating.

1933		Eve. Sun (Baltimore, MD) 9 Dec. 31/5: Scarf — food.
1936		D. Burley in Chicago Defender 25 July 22: dictionary additions: Scarf [...] to dine: act of doing the same.
1944		D. Burley Orig. Hbk of Harlem Jive 146: scarf [...] food, meat, dinner.
1953		L. Durst Jives of Dr. Hepcat (1989) 6: The scarf is low at the castle, my fronts are on the thin side, my stomps got eyes, the landlord is putting down a clown for his scratch.
1967		M. Braly On the Yard (2002) 250: If you want coffee, or some scarf — help yourself.

In phrases

knock a scarf (v.)

(US black) to eat.

1938		D. Burley N.Y. Amsterdam News 29 Jan. 19/1: ’Tis an abrupt bring-down to ‘knock a scarf’ with weakfish!
1942		Pittsburgh Courier (PA) 22 Aug. 7/5: I am going to knock me a scarf — I m going to get something to eat.
1953		L. Durst Jives of Dr. Hepcat (1989) 1: Now your girl friend calls you up, and you have to bathe and eat before you are ready for a show date. ‘Knock a statue act chick, I’ve got to make like a fish and knock a scarf and then we can cruise on over to the righteous flick.’.