chickadee » lmdb-lolevel » mdb-cursor-open

mdb-cursor-open txn dbiprocedure

Create a cursor handle.

A cursor is associated with a specific transaction and database. A cursor cannot be used when its database handle is closed. Nor when its transaction has ended, except with (mdb-cursor-renew). It can be discarded with (mdb-cursor-close). A cursor in a write-transaction can be closed before its transaction ends, and will otherwise be closed when its transaction ends. A cursor in a read-only transaction must be closed explicitly, before or after its transaction ends. It can be reused with (mdb-cursor-renew) before finally closing it.

A transaction handle returned by (mdb-txn-begin)
A database handle returned by (mdb-dbi-open)

Some possible error conditions:

(exn lmdb EINVAL)
an invalid parameter was specified