ct_br_column uses a CS_BROWSEDESC structure to return information about a browse mode column. Browse mode columns are returned by a Transact-SQL select ... for browse statement.
See the “Browse Mode” topics page in the Open Client Client-Library/C Reference Manual.
For a description of the fields in a CS_BROWSEDESC structure, see the “CS_BROWSEDESC Structure” topics page in the Open Client Client-Library/C Reference Manual.