[issue1731717] race condition in subprocess module
Yonas yona...@gmail.com added the comment: Florent, Have you tested any of the sample test programs mentioned in this bug report? For example, the one by Joel Martin (kanaka). I'd suggest to test those first before marking this issue as fixed. - Yonas -- status: pending - open ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue1731717 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1731717] race condition in subprocess module
Yonas yona...@gmail.com added the comment: http://groups.google.com/group/comp.lang.python/browse_thread/thread/9a853d0308c8e55a I'm also glad to see a test case that causes exactly the same error with or without the presence of a ‘daemon.DaemonContext’. Further research shows that handling of ‘SIGCLD’ (or ‘SIGCLD’) is fairly OS-specific, with “ignore it” or “handle it specifically” being correct on different systems. I think Python's default handling of this signal is already good (modulo bug #1731717 to be addressed in ‘subprocess’). So I will apply a change similar to Joel Martin's suggestion, to default to avoid touching the ‘SIGCLD’ signal at all, and with extra notes in the documentation that anyone using child processes needs to be wary of signal handling. This causes the above test case to succeed; the output file contains:: = Child process via os.system. Child process via 'subprocess.Popen'. Parent daemon process. Parent daemon process done. = -- By Ben Finney -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue1731717 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1731717] race condition in subprocess module
Yonas yona...@gmail.com added the comment: Ben Finney's comment suggests to me that this bug is being ignored. Am I wrong? with extra notes in the documentation that anyone using child processes needs to be wary of signal handling. Why should they be wary? We should just fix this bug. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue1731717 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1731717] race condition in subprocess module
Yonas yona...@gmail.com added the comment: By the way, in three months from today, this bug will be 3 years old. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue1731717 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1731717] race condition in subprocess module
Yonas yona...@gmail.com added the comment: Gregory, Awesome! Approx. how long until we hear back from you in this report? -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue1731717 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1731717] race condition in subprocess module
Yonas yona...@gmail.com added the comment: To test with exim4 is easy. To reproduce on Ubuntu Jaunty: 1. apt-get install exim4-daemon-heavy 2. echo local_scan = /usr/lib/exim4/local_scan/libpyexim.so /etc/exim4/conf.d/main/15_py-exim_plugin_path 3. cd /usr/lib/exim4/local_scan 4. Compile mylib, output will be libpyexim.so: gcc `python2.6-config --cflags` -c -fPIC mylib.c -o mylib.o gcc -Xlinker -export-dynamic -lpython2.6 -lnsl -lpthread -ldl -lutil -lm -lz -shared -Wl,-soname,libpyexim.so -o libpyexim.so mylib.o 5. Restart server: /etc/init.d/exim4 restart 6. Send some mail: cat mail.txt | sendmail -t (contents of mail.txt): Content-type: text/plain To: your_usern...@localhost From: foo...@example.com Subject: test Hello world. -- status: pending - open ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue1731717 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1731717] race condition in subprocess module
Yonas yona...@gmail.com added the comment: Also, copy exim_local_scan2.py to /usr/lib/python2.6/ -- Added file: http://bugs.python.org/file14134/exim_local_scan2.py ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue1731717 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1731717] race condition in subprocess module
Yonas yona...@gmail.com added the comment: I'm assuming that exim4 is reading config files from /etc/exim4/conf.d/*. To make sure, you can enforce split file mode by running `sudo dpkg-reconfigure exim4-config`. It should be one of the last questions present to you. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue1731717 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1731717] race condition in subprocess module
Yonas yona...@gmail.com added the comment: I always get a subprocess error when using embedded python 2.6.2: File /usr/lib/python2.6/subprocess.py, line 1123, in wait: pid, sts = os.waitpid(self.pid, 0): OSError: [Errno 10] No child processes Example library and main program are attached. -- nosy: +yonas Added file: http://bugs.python.org/file14086/mylib.c ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue1731717 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue1731717] race condition in subprocess module
Changes by Yonas yona...@gmail.com: Added file: http://bugs.python.org/file14087/main.c ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue1731717 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] [Errno 10] No child processes
New submission from Yonas yona...@gmail.com: I always get a subprocess error when using embedded Python 2.6.2: File /usr/lib/python2.6/subprocess.py, line 1123, in wait: pid, sts = os.waitpid(self.pid, 0): OSError: [Errno 10] No child processes Sample library and main files attached. -- files: mylib.c messages: 88407 nosy: yonas severity: normal status: open title: [Errno 10] No child processes versions: Python 2.6 Added file: http://bugs.python.org/file14088/mylib.c ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] [Errno 10] No child processes
Changes by Yonas yona...@gmail.com: Added file: http://bugs.python.org/file14089/main.c ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] OSError: [Errno 10] No child processes
Changes by Yonas yona...@gmail.com: -- title: [Errno 10] No child processes - OSError: [Errno 10] No child processes ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] OSError: [Errno 10] No child processes
Changes by Yonas yona...@gmail.com: -- type: - crash ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] OSError: [Errno 10] No child processes
Yonas yona...@gmail.com added the comment: The test doesn't fail when run directly from ./main, but it fails when run from exim4 mail server. exim will dlopen() mylib and run local_scan(). Besides using Popen, I haven't had any problems. -- Added file: http://bugs.python.org/file14094/exim_local_scan2.py ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] OSError: [Errno 10] No child processes
Yonas yona...@gmail.com added the comment: Thanks for testing, it works when running ./main, but not when run through exim. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] OSError: [Errno 10] No child processes
Yonas yona...@gmail.com added the comment: I didn't find anything unusual about how exim uses dlopen, but if you want to see the code, it's here: http://pastebin.com/m52398b30 Line 166 is the actual call. Again, no problems except with Python's Popen(). -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] OSError: [Errno 10] No child processes
Yonas yona...@gmail.com added the comment: Could this be a permissions issue? I have no idea how permissions would effect it, though... r...@yonas-laptop:/usr/lib/exim4/local_scan# ls -la /usr/sbin/exim4 -rwsr-xr-x 1 root root 824440 2009-02-11 08:53 /usr/sbin/exim4 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] OSError: [Errno 10] No child processes
Yonas yona...@gmail.com added the comment: os.system() works: os.system(echo `date` /tmp/myfile) r...@yonas-laptop:/usr/lib/exim4/local_scan# cat /tmp/myfile Wed May 27 16:04:54 EDT 2009 Wed May 27 16:04:54 EDT 2009 -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] OSError: [Errno 10] No child processes
Yonas yona...@gmail.com added the comment: Here's another test, taken from the docs: http://docs.python.org/library/subprocess.html#subprocess-replacements: This is slightly better than Popen because the program executes and shows output, but worse than os.system(), because it still shows the error: -- try: retcode = call(echo + \hello world\, shell=True) if retcode 0: print sys.stderr, Child was terminated by signal, -retcode print sys.stderr, Child was terminated by signal, -retcode else: print sys.stderr, Child returned, retcode except OSError, e: print sys.stderr, Execution failed:, e - hello world Execution failed: [Errno 10] No child processes -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue6122] OSError: [Errno 10] No child processes
Changes by Yonas yona...@gmail.com: -- versions: +Python 2.5, Python 3.0 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue6122 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue4434] Embedding into a shared library fails
Yonas yona...@gmail.com added the comment: Ralf, Linking against the static library (with '-Xlinker -export-dynamic') did _not_ solve the problem for me. gcc `python2.6-config --cflags` -c -fPIC mylib.c -o mylib.o -Xlinker -export-dynamic gcc -Xlinker -export-dynamic -lpthread -ldl -lutil -lm -lz -shared -Wl,-soname,mylib.so -o mylib.so mylib.o /usr/lib/python2.6/config/libpython2.6.a gcc `python2.6-config --cflags` -Xlinker -export-dynamic -ldl -lutil -lm -lz -o main main.c /usr/lib/python2.6/config/libpython2.6.a -- `python2.6-config --cflags` returns -I/usr/include/python2.6 -I/usr/include/python2.6 -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes Ubuntu Jaunty Linux yonas-laptop 2.6.28-11-generic #42-Ubuntu SMP Fri Apr 17 01:57:59 UTC 2009 i686 GNU/Linux -- nosy: +yonas ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue4434 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue4434] Embedding into a shared library fails
Yonas yona...@gmail.com added the comment: Same error message: import dl: ImportError: /usr/lib/python2.6/lib-dynload/dl.so: undefined symbol: PyExc_ValueError -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue4434 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue4434] Embedding into a shared library fails
Yonas yona...@gmail.com added the comment: Here's my log file (`LD_DEBUG=all ./main`) -- Added file: http://bugs.python.org/file14033/log-main.txt ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue4434 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue4434] Embedding into a shared library fails
Changes by Yonas yona...@gmail.com: Removed file: http://bugs.python.org/file14033/log-main.txt ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue4434 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue4434] Embedding into a shared library fails
Yonas yona...@gmail.com added the comment: Updated log file. -- Added file: http://bugs.python.org/file14034/log-main.txt ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue4434 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue4434] Embedding into a shared library fails
Yonas yona...@gmail.com added the comment: rb's workaround works, though. -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue4434 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
