# Archive
An archive is one addressable unit of an index, and holds one or more {ref}`TFile` records.

{ref}`EConfigArchive` names the archives of the config index, which is where item, object and
npc definitions live.


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## Archive.Create
```pascal
function TArchive.Create(id: Integer): TArchive; static;
function TArchive.Create(id, hashName: Integer): TArchive; static; overload;
```
An empty archive with the given id, and optionally the hash of its name - see
{ref}`CacheString2Hash`. A named archive is assumed to be gzipped, which is what the cache uses
for everything it names.


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## Archive.Read
```pascal
procedure TArchive.Read(const data: TByteArray);
```
Splits an archive's decompressed bytes across the files it holds.

An archive with one file is that file. With more than one, the bytes are interleaved in chunks -
a piece of every file, then another piece of every file - and a table at the end gives each
piece's size as a delta from the piece before it. So the sizes are summed in a first pass to
allocate each file, and a second pass copies the pieces into place, each file carrying how far
into its buffer the next piece goes.