| 59 | self.pid = forkserver.read_signed(self.sentinel) |
| 60 | |
| 61 | def poll(self, flag=os.WNOHANG): |
| 62 | if self.returncode is None: |
| 63 | from multiprocessing.connection import wait |
| 64 | timeout = 0 if flag == os.WNOHANG else None |
| 65 | if not wait([self.sentinel], timeout): |
| 66 | return None |
| 67 | try: |
| 68 | self.returncode = forkserver.read_signed(self.sentinel) |
| 69 | except (OSError, EOFError): |
| 70 | # This should not happen usually, but perhaps the forkserver |
| 71 | # process itself got killed |
| 72 | self.returncode = 255 |
| 73 | |
| 74 | return self.returncode |