# Memory File Archive

## 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 gets loaded automatically the first time the FS_CreateFileFromMemory function is called. It gets accessed at the specified memory location by the MI_CpuCopy8 function and gets manipulated like 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). Also, the archive name is registered in the file system.
Operations are always conducted synchronously, even when the asynchronous versions of functions are called.

## Implementation

The Memory File Archive gets 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

06/28/2005 Initial version.

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