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 valid 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

Any error occured in low level disk I/O.

FR_NOT_READY

The disk drive cannot work due to no medium in the drive or any other reason.

FR_NOT_ENABLED

FatFs module is not enabled.

Description

The read/write pointer increases in number of bytes written. The ByteWritten will be 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