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[FreeRTOS Embedded File System API]

long f_tell( F_FILE *pxFileHandle );

Return the current read/write position of an open file in the FAT file system.


pxFileHandle   The handle of the file being queried. The handle is returned from the call to f_open() used to originally open the file.

-1   F_FS_THREAD_AWARE is set to 1 and a file system lock could not be obtained before F_MAX_LOCK_WAIT_TICKS elapsed.

Any other value.   The returned value is the current read/write position within the open file.

See also


Example usage:

void vSampleFunction( char *pcFileName, char *pcBuffer )
F_FILE *pxFile;
long lPosition;

    /* Open the file specified by the pcFileName parameter. */
    pxFile = f_open( pcFileName, "r" );

    /* Expect the file position to be 0. */
    lPosition = f_tell( pxFile );

    /* Read one byte. */
    f_read( pcBuffer, 1, 1, pxFile );

    /* Expect the file position to be 1. */
    lPosition = f_tell( pxFile );

    /* Read another byte. */
    f_read( pcBuffer, 1, 1, pxFile );

    /* Expect the file position to be 2. */
    lPosition = f_tell( pxFile );

    /* Close the file again. */
    f_close( pxFile );
Example use of the f_tell() API function

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