- changed the nt.popen2 return values back to

(write, read, ...), based on feedback from GvR.

- added tuple-swapping code to popen2.py

- fixed some runaway indentation in posixmodule.c

Lib/popen2.py

@@ -89,9 +89,14 @@ class Popen3:
             _active.remove(self)
         return self.sts
 
-try:
+if hasattr(os, "popen2"):
-    from os import popen2
+    def popen2(cmd, mode='t', bufsize=-1):
-except NameError:
+        """Execute the shell command 'cmd' in a sub-process.  If 'bufsize' is
+        specified, it sets the buffer size for the I/O pipes.  The file objects
+        (child_stdout, child_stdin) are returned."""
+        w, r = os.popen2(cmd, mode, bufsize)
+        return r, w
+else:
     def popen2(cmd, mode='t', bufsize=-1):
         """Execute the shell command 'cmd' in a sub-process.  If 'bufsize' is
         specified, it sets the buffer size for the I/O pipes.  The file objects
@@ -104,9 +109,14 @@ except NameError:
         inst = Popen3(cmd, 0, bufsize)
         return inst.fromchild, inst.tochild
 
-try:
+if hasattr(os, "popen3"):
-    from os import popen3
+    def popen3(cmd, mode='t', bufsize=-1):
-except NameError:
+        """Execute the shell command 'cmd' in a sub-process.  If 'bufsize' is
+        specified, it sets the buffer size for the I/O pipes.  The file objects
+        (child_stdout, child_stdin, child_stderr) are returned."""
+        w, r, e = os.popen3(cmd, mode, bufsize)
+        return r, w, e
+else:
     def popen3(cmd, mode='t', bufsize=-1):
         """Execute the shell command 'cmd' in a sub-process.  If 'bufsize' is
         specified, it sets the buffer size for the I/O pipes.  The file objects
@@ -119,10 +129,15 @@ except NameError:
         inst = Popen3(cmd, 1, bufsize)
         return inst.fromchild, inst.tochild, inst.childerr
 
-try:
+if hasattr(os, "popen4"):
-    from os import popen4
+    def popen4(cmd, mode='t', bufsize=-1):
-except NameError:
+        """Execute the shell command 'cmd' in a sub-process.  If 'bufsize' is
-    pass # not on unix
+        specified, it sets the buffer size for the I/O pipes.  The file objects
+        (child_stdout_stderr, child_stdin) are returned."""
+        w, r = os.popen4(cmd, mode, bufsize)
+        return r, w
+else:
+    pass # not yet on unix
 
 def _test():
     teststr = "abc\n"

Modules/posixmodule.c

@@ -2419,8 +2419,7 @@ _PyPopen(char *cmdstring, int mode, int n)
 
 	 fSuccess = DuplicateHandle(GetCurrentProcess(), hChildStdoutRd,
 				    GetCurrentProcess(), &hChildStdoutRdDup, 0,
-								FALSE,
+				    FALSE, DUPLICATE_SAME_ACCESS);
-								DUPLICATE_SAME_ACCESS);
 	 if (!fSuccess)
 		 return win32_error("DuplicateHandle", NULL);
 
@@ -2431,10 +2430,11 @@ _PyPopen(char *cmdstring, int mode, int n)
 	 if (n != POPEN_4) {
 		 if (!CreatePipe(&hChildStderrRd, &hChildStderrWr, &saAttr, 0))
 			 return win32_error("CreatePipe", NULL);
-		 fSuccess = DuplicateHandle(GetCurrentProcess(), hChildStderrRd,
+		 fSuccess = DuplicateHandle(GetCurrentProcess(),
-									GetCurrentProcess(), &hChildStderrRdDup, 0,
+					    hChildStderrRd,
-									FALSE,
+					    GetCurrentProcess(),
-									DUPLICATE_SAME_ACCESS);
+					    &hChildStderrRdDup, 0,
+					    FALSE, DUPLICATE_SAME_ACCESS);
 		 if (!fSuccess)
 			 return win32_error("DuplicateHandle", NULL);
 		 /* Close the inheritable version of ChildStdErr that we're using. */
@@ -2516,7 +2516,7 @@ _PyPopen(char *cmdstring, int mode, int n)
 		 if (n != 4)
 			 CloseHandle(hChildStderrRdDup);
 
-		 f = Py_BuildValue("OO",p2,p1);
+		 f = Py_BuildValue("OO",p1,p2);
 		 break;
 	 }
 	
@@ -2545,7 +2545,7 @@ _PyPopen(char *cmdstring, int mode, int n)
 		 PyFile_SetBufSize(p1, 0);
 		 PyFile_SetBufSize(p2, 0);
 		 PyFile_SetBufSize(p3, 0);
-		 f = Py_BuildValue("OOO",p2,p1,p3);
+		 f = Py_BuildValue("OOO",p1,p2,p3);
 		 break;
 	 }
 	 }