77         ProcessManager::fork(frame, CloneFlags::empty()).map(|pid| pid.into())  in fork()
143         pid: i64,  in wait4()
166         let r = kernel_wait4(pid, wstatus_buf, options, tmp_rusage.as_mut())?;  in wait4()
206     pub fn getpgid(mut pid: Pid) -> Result<Pid, SystemError> {  in getpgid()
207         if pid == Pid(0) {  in getpgid()
209             pid = current_pcb.pid();  in getpgid()
211         let target_proc = ProcessManager::find(pid).ok_or(SystemError::ESRCH)?;  in getpgid()
245         procfs_register_pid(pcb.pid()).unwrap_or_else(|e| {  in clone()
248                 pcb.pid(),  in clone()
261             writer.copy_one_to_user(&(pcb.pid().data() as i32), 0)?;  in clone()
267                 pcb.pid(),  in clone()
277         return Ok(pcb.pid().0);  in clone()
287         Ok(pcb.pid.0)  in set_tid_address()
292         Ok(pcb.pid)  in gettid()