What time does the library open?

"What time does the library open?" the man on the phone asked.
"Nine A.M." came the reply. "And what's the idea of calling me at home in the middle of the night to ask a question like that?"
"Not until nine A.M.?" the man asked in a disappointed voice.
"No, not till nine A.M.!" the librarian said. "Why do you want to get in before nine A.M.?"
"Who said I wanted to get in?" the man sighed sadly. "I want to get out."