SF patch #489173: Make os.spawnv not block the interpreter, from
Anthony Roach.
Release the global interpreter lock around platform spawn calls.
Bugfix candidate? Hard to say; I favor "yes, bugfix".
These clearly *should* have been releasing the GIL all along, if for no
other reason than compatibility with the similar os.system(). But it's
possible some program out there is (a) multithreaded, (b) calling a spawn
function with P_WAIT, and (c) relying on the spawn call to block all their
threads until the spawned program completes. I think it's very unlikely
anyone is doing that on purpose, but someone may be doing so by accident.
diff --git a/Misc/ACKS b/Misc/ACKS
index 1ee3f0c..e110f15 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -353,6 +353,7 @@
Armin Rigo
Nicholas Riley
Jean-Claude Rimbault
+Anthony Roach
Andy Robinson
Jim Robinson
Kevin Rodgers
diff --git a/Misc/NEWS b/Misc/NEWS
index 6dd9957..6df0b52 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -52,6 +52,13 @@
Library
+- Functions in the os.spawn() family now release the global interpreter
+ lock around calling the platform spawn. They should always have done
+ this, but did not before 2.2c1. Multithreaded programs calling
+ an os.spawn function with P_WAIT will no longer block all Python threads
+ until the spawned program completes. It's possible that some programs
+ relies on blocking, although more likely by accident than by design.
+
- webbrowser defaults to netscape.exe on OS/2 now.
- Tix.ResizeHandle exposes detach_widget, hide, and show.
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index bb55762..ebda8bf 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -1668,7 +1668,7 @@
#ifdef HAVE_SPAWNV
static char posix_spawnv__doc__[] =
"spawnv(mode, path, args)\n\
-Execute an executable path with arguments, replacing current process.\n\
+Execute the program 'path' in a new process.\n\
\n\
mode: mode of process creation\n\
path: path of executable file\n\
@@ -1717,8 +1717,11 @@
if (mode == _OLD_P_OVERLAY)
mode = _P_OVERLAY;
+
+ Py_BEGIN_ALLOW_THREADS
spawnval = _spawnv(mode, path, argvlist);
-
+ Py_END_ALLOW_THREADS
+
PyMem_DEL(argvlist);
if (spawnval == -1)
@@ -1734,7 +1737,7 @@
static char posix_spawnve__doc__[] =
"spawnve(mode, path, args, env)\n\
-Execute a path with arguments and environment, replacing current process.\n\
+Execute the program 'path' in a new process.\n\
\n\
mode: mode of process creation\n\
path: path of executable file\n\
@@ -1830,7 +1833,11 @@
if (mode == _OLD_P_OVERLAY)
mode = _P_OVERLAY;
+
+ Py_BEGIN_ALLOW_THREADS
spawnval = _spawnve(mode, path, argvlist, envlist);
+ Py_END_ALLOW_THREADS
+
if (spawnval == -1)
(void) posix_error();
else