Green’s Dictionary of Slang

1. a general phr. of greeting; a question mark is assumed even if not present; often answered by ‘all right’ or ‘not so bad’.

1868		D.M. Mulock in Good Words June 335/2: William's first greeting at his own door was always his wife's face... ‘All right, my darling?’.
1977		G.F. Newman Villain’s Tale 25: Harrington climbed out, and after nervously glancing about went and climbed into the 1100. ‘All right?’ Lynn enquired generally.
1985		J. Sullivan ‘Watching the Girls go by’ Only Fools and Horses [TV script] del: Alright Tommy? tommy: Hello Del.
1995		J. Cameron Vinnie Got Blown Away 45: All right Nicky? Lager?
2005		B. Hare Urban Grimshaw 41: All right, Urb? What’s up?

2. a coded query: do you need any drugs?

1997

N. Barlay Curvy Lovebox 187: Y’alrigh’? he says without lookin’.