TIVA DK-TM4C123G interface with USB flash drive

Hi,

I have been trying to create a text file in pendrive via USB in TIVA DK-TM4C123G development kit. I have made initializations required for USB. I am able to create a directory using f_mkdir() . Whereas I am not able to create a file using f_open(). Can anybody help me with a sample code to create and write data to a text file in TIVA DK-TM4C123G .

static FATFS g_sFatFs;
static DIR g_sDirObject;
static FILINFO g_sFileInfo;

extern FRESULT f_mkdir(const TCHAR *);
extern FRESULT f_write(FIL *,const void *,UINT,UINT *);
extern FRESULT f_open (FIL *,const TCHAR *,BYTE);

FRESULT fr1;
FRESULT fr;
FIL fil;
FIL fil1;
UINT bw;

fr = f_mkdir("my_file1");                         // creates a directory with name my_file1

fr1 = f_open(&fil1,"hi.txt",FA_CREATE_ALWAYS|FA_WRITE);

Thanks in advance...