f_write

The f_write writes data to a file.

FRESULT f_write (
  FIL* FileObject,     /* Pointer to the file object structure */
  const void* Buffer,  /* Pointer to the data to be written */
  WORD ByteToWrite,    /* Number of bytes to write */
  WORD* ByteWritten    /* Pointer to the variable to return number of bytes written */
);

Parameter

FileObject
Pointer to the open file object structure.
Buffer
Pointer to the data to be written.
ByteToWrite
Specifies number of bytes to write.
ByteWritten
Pointer to the WORD variable to return number of bytes written.

Return Values

FR_OK (0)
The function succeeded.
FR_DENIED
The function denied due to the file has been opened in read only mode.
FR_RW_ERROR
The function failed due to a disk error or an internal error.
FR_NOT_READY
The disk drive cannot work due to no medium in the drive or any other reason.
FR_INVALID_OBJECT
The file object is invalid.

Description

The read/write pointer in the file object is increased in number of bytes written. The ByteWritten will become less than ByteToWrite when disk gets full during write function. This function is not supported in read-only configuration.

References

f_open, f_read, f_close, FIL

Return