78     pub fn check_rw_param(&self, len: usize, buf: &[u8]) -> Result<(), SystemError> {  in check_rw_param()
79         if len > buf.len() {  in check_rw_param()
145         len: usize,  in read_at()
156         self.check_rw_param(len, buf)?;  in read_at()
159         let r: Result<usize, TtyError> = self.core.read_stdin(&mut buf[0..len], true);  in read_at()
179         len: usize,  in write_at()
191         self.check_rw_param(len, buf)?;  in write_at()
195             self.core.stdout(&buf[0..len], true)  in write_at()
197             self.core.stderr(&buf[0..len], true)  in write_at()
243             let len;  in sync()  localVariable
246                     len = x;  in sync()
249                     len = x;  in sync()
254             if len == 0 {  in sync()