It is a somewhat expensive operation, especially for an in-memory database. Dbzcancel cancels any pending writes from buffers. This is typically useful only for in-core databases, since writes are otherwise done immediately. Its main purpose is to let a child process, in the wake of a fork , do a dbmclose without writing its parent's data to disk. The database files include a record of the byte order of the processor creating the database, and accesses by processors with different byte order will work, although they will be slightly slower.
Byte order is preserved by dbzagain .
However, agreement on the size and internal structure of an fseek offset is necessary, as is consensus on the character set. Functions returning datum values return a value with dptr set to NULL for failure. Dbminit attempts to have errno set plausibly on return, but otherwise this is not guaranteed. An errno of EDOM from dbminit indicates that the database did not appear to be in dbz format. Later contributions by David Butler and Mark Moraes.