fn header_mut_ptr(&mut self, ix: u64) -> &mut Header {
        let ix = (ix * self.cell_size) as usize;
        let hdr_slice: &mut [u8] = &mut self.mmap[ix..ix + std::mem::size_of::<Header>()];
        unsafe {
            let hdr = hdr_slice.as_mut_ptr() as *mut Header;
            hdr.as_mut().unwrap()
        }
    }
/// return ref to header of item 'ix' in mmapped file
return ref to header of item 'ix' in mmapped file
return ref to header of item ' ix ' in mmapped file
fn header_mut_ptr(&mut self, ix: u64) -> &mut Header {
        let ix = (ix * self.cell_size) as usize;
        let hdr_slice: &mut [u8] = &mut self.mmap[ix..ix + std::mem::size_of::<Header>()];
        unsafe {
            let hdr = hdr_slice.as_mut_ptr() as *mut Header;
            hdr.as_mut().unwrap()
        }
    }
fn header_mut_ptr ( & mut self , ix : u64 ) -> & mut Header { let ix = ( ix * self . cell_size ) as usize ; let hdr_slice : & mut [ u8 ] = & mut self . mmap [ ix .. ix + std :: mem :: size_of :: < Header > ( ) ] ; unsafe { let hdr = hdr_slice . as_mut_ptr ( ) as * mut Header ; hdr . as_mut ( ) . unwrap ( ) } }
return ref to header of item 'ix' in mmapped file
return ref to header of item ' ix ' in mmapped file
&mut self
ix
u64