# FS_GetOverlayFileID

## Syntax

  `#include <nitro/fs.h>`
  `FSFileID FS_GetOverlayFileID(const FSOverlayInfo *p_ovi);`

## Arguments

p_ovi | `FSOverlayInfo` structure that holds overlay module information.

## Return Values

Returns the ID of the file in which the image of the overlay module is stored.

## Description

This function acquires the ID of the file in which the image of the overlay module has been stored. `FS_LoadOverlayInfo` loads the image from this file internally. Note that the file that is opened using the ID that this function returns is not in the directory hierarchy. Therefore, a failure occurs when the `FS_GetPathName` function is called for this file. It is possible to load overlays asynchronously by loading the file using the file ID returned by this function after using `FS_ClearOverlayImage()` to initialize the address returned by `FS_GetOverlayAddress()`.

## See Also

``FSOverlayInfo`
`FS_LoadOverlayInfo`
`FS_GetOverlayAddress`
`FS_LoadOverlayImage`
FS_StartOverlay`

## Revision History

2004/11/17 Revisions due to the elimination of the `FS_RegisterOverlayToDebugger` function.
2004/10/19 Added description regarding the `FS_RegisterOverlayToDebugger` function.
2004/06/11 Initial version.

CONFIDENTIAL