1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
import os
import sys
import signal
from . import util
__all__ = ['Popen']
#
# Start child process using fork
#
class Popen(object):
method = 'fork'
def __init__(self, process_obj):
sys.stdout.flush()
sys.stderr.flush()
self.returncode = None
self._launch(process_obj)
def duplicate_for_child(self, fd):
return fd
def poll(self, flag=os.WNOHANG):
if self.returncode is None:
while True:
try:
pid, sts = os.waitpid(self.pid, flag)
except OSError as e:
# Child process not yet created. See #1731717
# e.errno == errno.ECHILD == 10
return None
else:
break
if pid == self.pid:
if os.WIFSIGNALED(sts):
self.returncode = -os.WTERMSIG(sts)
else:
assert os.WIFEXITED(sts)
self.returncode = os.WEXITSTATUS(sts)
return self.returncode
def wait(self, timeout=None):
if self.returncode is None:
if timeout is not None:
from multiprocessing.connection import wait
if not wait([self.sentinel], timeout):
return None
# This shouldn't block if wait() returned successfully.
return self.poll(os.WNOHANG if timeout == 0.0 else 0)
return self.returncode
def terminate(self):
if self.returncode is None:
try:
os.kill(self.pid, signal.SIGTERM)
except ProcessLookupError:
pass
except OSError:
if self.wait(timeout=0.1) is None:
raise
def _launch(self, process_obj):
code = 1
parent_r, child_w = os.pipe()
self.pid = os.fork()
if self.pid == 0:
try:
os.close(parent_r)
code = process_obj._bootstrap()
finally:
os._exit(code)
else:
os.close(child_w)
util.Finalize(self, os.close, (parent_r,))
self.sentinel = parent_r
|