50     : pid_(0),  in ProcessImpl()
321   if (pid_ == 0) {  in Wait()
325   if (HANDLE_EINTR(waitpid(pid_, &status, 0)) < 0) {  in Wait()
327     LOG(ERROR) << "Problem waiting for pid " << pid_ << ": " << saved_errno;  in Wait()
330   pid_t old_pid = pid_;  in Wait()
352   return pid_;  in pid()
356   if (pid_ == 0) {  in Kill()
361   if (kill(pid_, signal) < 0) {  in Kill()
362     PLOG(ERROR) << "Unable to send signal to " << pid_;  in Kill()
368     pid_t w = waitpid(pid_, &status, WNOHANG);  in Kill()
381   LOG(INFO) << "process " << pid_ << " did not exit from signal " << signal  in Kill()
387   pid_ = new_pid;  in UpdatePid()
398   if (pid_)  in Reset()
420   pid_t old_pid = pid_;  in Release()
421   pid_ = 0;  in Release()