Issue #12502: asyncore: fix polling loop with AF_UNIX sockets.

Lib/asyncore.py

@@ -130,7 +130,8 @@ def poll(timeout=0.0, map=None):
             is_w = obj.writable()
             if is_r:
                 r.append(fd)
-            if is_w:
+            # accepting sockets should not be writable
+            if is_w and not obj.accepting:
                 w.append(fd)
             if is_r or is_w:
                 e.append(fd)
@@ -177,7 +178,8 @@ def poll2(timeout=0.0, map=None):
             flags = 0
             if obj.readable():
                 flags |= select.POLLIN | select.POLLPRI
-            if obj.writable():
+            # accepting sockets should not be writable
+            if obj.writable() and not obj.accepting:
                 flags |= select.POLLOUT
             if flags:
                 # Only check for exceptions if object was either readable

Misc/NEWS

@@ -22,6 +22,8 @@ What's New in Python 3.1.4?
 Library
 -------
 
+- Issue #12502: asyncore: fix polling loop with AF_UNIX sockets.
+
 - Issue #12009: Fixed regression in netrc file comment handling.
 
 Extension Modules