# MB_UnregisterFile

## Syntax

  `#include <nitro/mb.h>`
  `void* MB_UnregisterFile(const MBGameRegistry *game_reg);`

## Arguments

game_reg | Pointer to a `MBGameRegistry` structure that stores the information of the registered program to unregister.

## Return Values

Returns a pointer if it successfully unregisters the registered program. Otherwise, it returns NULL.

## Description

This function unregisters a specified, registered program from the download program list. As part of this unregistration process, the segment information's memory buffer specified by the `MB_RegisterFile` function will be released to the user side.

## Note

The `MB_RegisterFile` function cannot be called after this function has been called once or more.
To change the program's registered contents, you must first temporarily close the MB library by calling the `MB_End` function, change the TGID, and then restart the library.

## See Also

`MBGameRegistry, MB_GetSegmentLength, MB_ReadSegment, MB_RegisterFile`

## Revision History

2004/10/18 Added a Caution about the restriction affecting `MB_RegisterFile`.
2004/09/30 Changed return values.
2004/09/09 Initial version.

CONFIDENTIAL