pub fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
        let n = self.read_at(buf, self.pos)?;
        self.pos += n as u64;
        Ok(n)
    }
/// Read data and advance file position.
Read data and advance file position.
Read data and advance file position .
pub fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
        let n = self.read_at(buf, self.pos)?;
        self.pos += n as u64;
        Ok(n)
    }
pub fn read ( & mut self , buf : & mut [ u8 ] ) -> io :: Result < usize > { let n = self . read_at ( buf , self . pos ) ? ; self . pos += n as u64 ; Ok ( n ) }
Read data and advance file position.
Read data and advance file position .
&mut self
buf
&mut [u8]
&mut self
buf
&mut [u8]