- mdb-env-copyfd2 env fd flagsprocedure
Copy an LMDB environment to the specified file descriptor, with options.
This function may be used to make a backup of an existing environment. No lockfile is created, since it gets recreated at need. See (mdb-env-copy2) for further details.
Note: This call can trigger significant file size growth if run in parallel with write transactions, because it employs a read-only transaction. See long-lived transactions under Caveats in the C API documentation.
- An environment handle returned by (mdb-env-create). It must have already been opened successfully.
- The filedescriptor to write the copy to. It must have already been opened for Write access.
- Special options for this operation. See (mdb-env-copy2) for options.