From 9c4f44f70acadd70fcdb0a0d5d66cefbc9da20bf Mon Sep 17 00:00:00 2001
From: "Gregory P. Smith" <greg@krypto.org>
Date: Tue, 15 Mar 2011 14:56:39 -0400
Subject: [PATCH] Fix issue #11432. if the stdin pipe is the same file
 descriptor as either stdout or stderr in the _posixsubprocess C extension
 module it would unintentionally close the fds and raise an error.

---
 Modules/_posixsubprocess.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Modules/_posixsubprocess.c b/Modules/_posixsubprocess.c
index 0f85da97cea..bf10cbb43e1 100644
--- a/Modules/_posixsubprocess.c
+++ b/Modules/_posixsubprocess.c
@@ -99,10 +99,10 @@ static void child_exec(char *const exec_array[],
     if (p2cread > 2) {
         POSIX_CALL(close(p2cread));
     }
-    if (c2pwrite > 2) {
+    if (c2pwrite > 2 && c2pwrite != p2cread) {
         POSIX_CALL(close(c2pwrite));
     }
-    if (errwrite != c2pwrite && errwrite > 2) {
+    if (errwrite != c2pwrite && errwrite != p2cread && errwrite > 2) {
         POSIX_CALL(close(errwrite));
     }