int DB_MPOOLFILE->sync(DB_MPOOLFILE *mpf);
The DB_MPOOLFILE->sync method writes all pages associated with the DB_MPOOLFILE, which were marked as modified using DB_MPOOLFILE->put or DB_MPOOLFILE->set, back to the source file. If any of the modified pages are also pinned (that is, this or another process currently refers to them), DB_MPOOLFILE->sync will ignore them.
The DB_MPOOLFILE->sync method returns a non-zero error value on failure and 0 on success.
The DB_MPOOLFILE->sync method may fail and return a non-zero error for errors specified for other Berkeley DB and C library or system functions. If a catastrophic error has occurred, the DB_MPOOLFILE->sync method may fail and return DB_RUNRECOVERY, in which case all subsequent Berkeley DB calls will fail in the same way.
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