Merged revisions 87695 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k
........
r87695 | antoine.pitrou | 2011-01-03 19:23:55 +0100 (lun., 03 janv. 2011) | 5 lines
Issue #10806, issue #9905: Fix subprocess pipes when some of the standard
file descriptors (0, 1, 2) are closed in the parent process. Initial
patch by Ross Lagerwall.
........
diff --git a/Lib/subprocess.py b/Lib/subprocess.py
index 4c235d9..2ecde0b 100644
--- a/Lib/subprocess.py
+++ b/Lib/subprocess.py
@@ -1051,14 +1051,17 @@
errread, errwrite)
- def _set_cloexec_flag(self, fd):
+ def _set_cloexec_flag(self, fd, cloexec=True):
try:
cloexec_flag = fcntl.FD_CLOEXEC
except AttributeError:
cloexec_flag = 1
old = fcntl.fcntl(fd, fcntl.F_GETFD)
- fcntl.fcntl(fd, fcntl.F_SETFD, old | cloexec_flag)
+ if cloexec:
+ fcntl.fcntl(fd, fcntl.F_SETFD, old | cloexec_flag)
+ else:
+ fcntl.fcntl(fd, fcntl.F_SETFD, old & ~cloexec_flag)
def _close_fds(self, but):
@@ -1128,21 +1131,25 @@
os.close(errpipe_read)
# Dup fds for child
- if p2cread is not None:
- os.dup2(p2cread, 0)
- if c2pwrite is not None:
- os.dup2(c2pwrite, 1)
- if errwrite is not None:
- os.dup2(errwrite, 2)
+ def _dup2(a, b):
+ # dup2() removes the CLOEXEC flag but
+ # we must do it ourselves if dup2()
+ # would be a no-op (issue #10806).
+ if a == b:
+ self._set_cloexec_flag(a, False)
+ elif a is not None:
+ os.dup2(a, b)
+ _dup2(p2cread, 0)
+ _dup2(c2pwrite, 1)
+ _dup2(errwrite, 2)
- # Close pipe fds. Make sure we don't close the same
- # fd more than once, or standard fds.
- if p2cread is not None and p2cread not in (0,):
- os.close(p2cread)
- if c2pwrite is not None and c2pwrite not in (p2cread, 1):
- os.close(c2pwrite)
- if errwrite is not None and errwrite not in (p2cread, c2pwrite, 2):
- os.close(errwrite)
+ # Close pipe fds. Make sure we don't close the
+ # same fd more than once, or standard fds.
+ closed = { None }
+ for fd in [p2cread, c2pwrite, errwrite]:
+ if fd not in closed and fd > 2:
+ os.close(fd)
+ closed.add(fd)
# Close all other fds, if asked for
if close_fds: