Wikipedia
Fudaishi
Fudaishi 傅大士 (a.k.a. Fu Ta-shih) was a Chinese Buddhist monk who was later deified as the Japanese patron deity of libraries. He is traditionally accredited with the invention of the , a system of revolving shelving used in Kyōzō libraries. He is often represented alongside his sons, Fuwaku and Fukon.
Fudaishi is noted for his "lecture" on the Diamond Sutra, recorded in the Hekiganroku (Record of the Blue Cliffs). According to this account, Fudaishi was invited to speak by the Emperor Bu-tei. He stepped up to the lectern, struck it a blow with his staff, and then returned to his seat without speaking a word.
He is regarded as in incarnation of Miroku, the Waiting Buddha.