128     pub fn read(&mut self, len: usize, buf: &mut [u8]) -> Result<usize, SystemError> {  in read()
132         if buf.len() < len {  in read()
141         let len = self  in read()  localVariable
143             .read_at(self.offset, len, buf, &mut self.private_data)?;  in read()
144         self.offset += len;  in read()
145         return Ok(len);  in read()
155     pub fn write(&mut self, len: usize, buf: &[u8]) -> Result<usize, SystemError> {  in write()
158         if buf.len() < len {  in write()
167         let len = self  in write()  localVariable
169             .write_at(self.offset, len, buf, &mut self.private_data)?;  in write()
170         self.offset += len;  in write()
171         return Ok(len);  in write()
279                 ::core::slice::from_raw_parts_mut::<'static, u8>(ptr, name_bytes.len());  in readdir()
284         return Ok((name_bytes.len() + ::core::mem::size_of::<Dirent>()  in readdir()
356     pub fn ftruncate(&mut self, len: usize) -> Result<(), SystemError> {  in ftruncate()
361         self.inode.resize(len)?;  in ftruncate()