cif_merge(1) on Linux
The text 9bc7bc3e41cd, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye) shipped it. The page shows this text now.
merge data values in identical data blocks of multiple CIFs. Unique data items are combined into a single data block of the output CIF; data items with equivalent values are silently merged into one. When a value differs for the same data item and the same data block in two files, a warning (error) is issued.