# Memory File Archives

## Overview

This section explains the Memory File Archive that is prepared by default in the file system.

## Specifications

The basic operations of the Memory File Archive are outlined below:
• It is loaded automatically the first time the `FS_CreateFileFromMemory` function is called.
• It is accessed at the memory location specified by the `MI_CpuCopy8` function, making it possible to manipulate it as a file.
Cache disabling and cleaning are not performed internally. Other than file reading/writing, it does not support any manipulations (general directory and path-related commands). The archive name is not registered in the file system.
Operations are always conducted synchronously, even when the asynchronous versions of functions are called.

## Implementation

The Memory File Archive is implemented as follows:
Read Callback: Data is read from memory by the `MI_CpuCopy8` function. The response is always `FS_RESULT_SUCCESS`.
Write Callback: Data is written to memory by the `MI_CpuCopy8` function. The response is always `FS_RESULT_SUCCESS`.
User Procedures:

`FS_COMMAND_SEEKDIR FS_COMMAND_READDIR FS_COMMAND_FINDPATH FS_COMMAND_GETPATH FS_COMMAND_OPENFILEFAST` | These commands are not supported. Issuing any of them always returns `FS_RESULT_UNSUPPORTED`.
Other | Returns `FS_RESULT_PROC_UNKNOWN` and defaults to default commands.

## See Also

`FSArchive
FS_ARCHIVE_PROC_FUNC
FS_SetArchiveProc`

## Revision History

2005/06/28 Initial version.

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