[3.6] bpo-30185: avoid KeyboardInterrupt tracebacks in forkserver (GH-1319) (#1454)
* bpo-30185: avoid KeyboardInterrupt tracebacks in forkserver
* Tweak comment.
(cherry picked from commit 6dd4d734ed207ba16b017e38f8909de7ef187e29)
diff --git a/Lib/multiprocessing/forkserver.py b/Lib/multiprocessing/forkserver.py
index f2c179e..d5ce625 100644
--- a/Lib/multiprocessing/forkserver.py
+++ b/Lib/multiprocessing/forkserver.py
@@ -149,8 +149,15 @@
util._close_stdin()
- # ignoring SIGCHLD means no need to reap zombie processes
- handler = signal.signal(signal.SIGCHLD, signal.SIG_IGN)
+ # ignoring SIGCHLD means no need to reap zombie processes;
+ # letting SIGINT through avoids KeyboardInterrupt tracebacks
+ handlers = {
+ signal.SIGCHLD: signal.SIG_IGN,
+ signal.SIGINT: signal.SIG_DFL,
+ }
+ old_handlers = {sig: signal.signal(sig, val)
+ for (sig, val) in handlers.items()}
+
with socket.socket(socket.AF_UNIX, fileno=listener_fd) as listener, \
selectors.DefaultSelector() as selector:
_forkserver._forkserver_address = listener.getsockname()
@@ -175,7 +182,7 @@
code = 1
if os.fork() == 0:
try:
- _serve_one(s, listener, alive_r, handler)
+ _serve_one(s, listener, alive_r, old_handlers)
except Exception:
sys.excepthook(*sys.exc_info())
sys.stderr.flush()
@@ -186,11 +193,12 @@
if e.errno != errno.ECONNABORTED:
raise
-def _serve_one(s, listener, alive_r, handler):
- # close unnecessary stuff and reset SIGCHLD handler
+def _serve_one(s, listener, alive_r, handlers):
+ # close unnecessary stuff and reset signal handlers
listener.close()
os.close(alive_r)
- signal.signal(signal.SIGCHLD, handler)
+ for sig, val in handlers.items():
+ signal.signal(sig, val)
# receive fds from parent process
fds = reduction.recvfds(s, MAXFDS_TO_SEND + 1)