morgrupo.blogg.se - Dbm out of date

The staleness counters each take two bytes (packed 32-bit It is therefore anywhere from 1 byte to 32 The transaction bitfield consists of one bit for everyĪvailable transaction ID. The number of transactions corresponds to the What is passed to the constructor, to allow for a range of 1-256. The number stored is actually one less than Three values are stored as packed 8-bit integers (chars), so 2 is

The byte size is the number of bytes used to point to an These are the file-wide constants that determine how the file The second part of the header is as follows: The size of the second part of the header, in bytes. It is packed in network order, so version 4 is stored as This is four bytes containing the file version. Theįile used by versions prior to 1.00 had a different fifth byte, allowing Signifying that this is a DBM::Deep file.Ī literal ASCII 'h', indicating that this is the header. The first four bytes are 'DPDB' in network byte order, \ '- size of the second part of the header These two formats are almost identical.ĭBM::Deep uses a tagged file layout. This describes the 1.0003 and 2.0000 formats, which internally are Place to handle datastructure-wide items, such as transactions. Singleton that every other object has a reference to, it also provides a

DBM::Deep::File is the layer that deals with the physical file.

This is where the logic of the file layout is

DBM::Deep::Engine is the layer that deals with the mechanics of readingĪnd writing to the file.

They are theĬlasses that provide the TIE mechanisms as well as the OO methods. TheseĬlasses form the immediate interface to the outside world.

DBM::Deep is the parent of DBM::Deep::Array and DBM::Deep::Hash.

Of specifics of how DBM::Deep works or who wish to help programĭBM::Deep is broken up into five classes in three inheritance This document is intended for people who either want a deeper understanding It is not necessary to read this document if you only intend to be a user. This is a document describing the internal workings of DBM::Deep.

So far, the description of the header format has been updated. It describes an intermediate fileįormat used during the development from 0.983 to 1.0000. DBM::Deep::Internals - Out of date documentation on DBM::Deep