+FAT get file name from FF_FILE

Libraries
1

Hello,

I am using the FreeRTOS+FAT driver for my data logger project. I would like to know if it is possible to get the filename if I have a handle to the file object FF_FILE*. I have tried digging deep into the +FAT source code but couldn’t quite find a straightforward way to do this.

Thank you,
Sid

2

Not sure it is possible. Can you keep a mapping between the FF_FILE variable and the name of the file opened when that value was returned within your application code?

3

Ah damn, feels like something so simple but I’m sure there are complications that will come with doing that.

My backup option was to create a struct that wraps together a FF_FILE item and the associated filename. I think I will just do this for now.

Thank you!

4

For anyone wondering why I need this, it is because I want to use the ff_remove function which only takes a file name as an argument and not a handle to the file. So like Richard said, I am going to keep a mapping between the name and the handle so that I can delete the file when needed.

5

It would be possible to derive the original filename by reading the directory in which the file appears.
The FF_FILE struct maintains two fields fir this:

  • ulDirCluster which is the cluster in which the directory can be found
  • usDirEntry the entry number within the directory

If I am not mistaken, the following code should do:

	FF_DirEnt_t xDirEntry;
	FF_Error_t xError;

    xError = FF_GetEntry( pxFile->pxIOManager, pxFile->usDirEntry, pxFile->ulDirCluster, &xDirEntry );
	if( FF_isERR( xError ) == pdFALSE )
	{
		printf( "The name is stored in: %s\n", xDirEntry.pcFileName );
	}

But as Richard noted, an easier ( and more compatible ) is to just remember the filename that belongs to the file handle. Up to you!

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