Definition of "gruffly"

Bradly squatted on the flat rock to wash his legs, saying gruffly to Podson, "Better wash that dam' mud off; it sticks like hell when it's dry."

1938, Norman Lindsay, Age of Consent, 1st Australian edition, Sydney, N.S.W.: Ure Smith, published 1962, page 66

'Hey, what's that?' he exclaimed gruffly, staring searchingly at her as he took her hand.

1956 , Johanna Spyri, Heidi, translation of original by Eileen Hall, page 48