mongoc_create_indexes(3) on Linux
The text 01396fe3b2fa, as Debian 10 (Buster) shipped it.
Creating Indexes To create indexes on a MongoDB collection, execute the createIndexes command with a command function like mongoc_database_write_command_with_opts or mongoc_collection_write_command_with_opts. See the MongoDB Manual entry for the createIndexes command for details.