From f2705aebb04a1c3f758d7f3383b981e1673525b7 Mon Sep 17 00:00:00 2001 From: "Gregory P. Smith" Date: Sat, 10 Nov 2012 21:13:20 -0800 Subject: [PATCH] Fixes issue #14396: Handle the odd rare case of waitpid returning 0 when not expected in subprocess.Popen.wait(). --- Lib/subprocess.py | 8 ++++++-- Misc/NEWS | 3 +++ 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/Lib/subprocess.py b/Lib/subprocess.py index 0f284d1f0d..8356782224 100644 --- a/Lib/subprocess.py +++ b/Lib/subprocess.py @@ -1303,7 +1303,7 @@ class Popen(object): def wait(self): """Wait for child process to terminate. Returns returncode attribute.""" - if self.returncode is None: + while self.returncode is None: try: pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0) except OSError as e: @@ -1312,8 +1312,12 @@ class Popen(object): # This happens if SIGCLD is set to be ignored or waiting # for child processes has otherwise been disabled for our # process. This child is dead, we can't get the status. + pid = self.pid sts = 0 - self._handle_exitstatus(sts) + # Check the pid and loop as waitpid has been known to return + # 0 even without WNOHANG in odd situations. issue14396. + if pid == self.pid: + self._handle_exitstatus(sts) return self.returncode diff --git a/Misc/NEWS b/Misc/NEWS index a670e2026c..c27f82955b 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -143,6 +143,9 @@ Core and Builtins Library ------- +- Issue #14396: Handle the odd rare case of waitpid returning 0 when not + expected in subprocess.Popen.wait(). + - Issue #16411: Fix a bug where zlib.decompressobj().flush() might try to access previously-freed memory. Patch by Serhiy Storchaka. -- 2.49.0