* Define Local Device.
*Fetch device from local device.
*Allocate space for buffer,pointed to by dev->data.
*Check for error ,clear the allocated space using memset.
*Check if the fpos is beyond the device size.
*Check for errors.
*Check if the sufficient amount of space is available to write the count no of bytes.
** if not modify the count accordingly.
*Copy from user.
*Modify the file position.
*Identify the no. of bytes yet to be written.
*Modify the device data size.
*Return space for buffer,pointed to by dev->data.
