Cambridge dicts said:used to ask how much of something someone has, or to ask about someone's arrangements:
How are you fixed for cash?
How are you fixed for Saturday evening?
Sinatra said:<Frank> How are ya fixed for moonlight ?
How are ya fixed for stars?
<Keely> How are you fixed for kissin' ?
While we listen to soft guitars?
talktidy.com said:How are you fixed? :
How are you placed?, as in "They're running a trip to the Panto on Tuesday - how are you fixed for going?"
Is it common? What did Frank mean by "...fixed for moonlight/stars" ?