Python script produces sem_trywait: Permission denied
Hi, I've seen this question posted many places arount the Internet, but I've not seen any answers. We've been seeing this same error for some time, probably as long as Hudson has (given that it's now mid-October 2005); we just ignored it, since it didn't seem to cause problems. However, if anyone does have a solution to it I'd like to see it. I hate having unresolved wierdnesses in our code. -- Mark E. Hamilton Orion International Technologies, Inc. Sandia National Laboratory, NM. 505-844-7666 -- http://mail.python.org/mailman/listinfo/python-list
Python script produces sem_trywait: Permission denied
Sorry, I probably should have re-stated the problem: We're using Python 2.3.5 on AIX 5.2, and get the follow error messages from some of our code. I haven't yet tracked down exactly where it's coming from: sem_trywait: Permission denied sem_wait: Permission denied sem_post: Permission denied We don't run these scripts as root, so I can't say whether they work as root. I suspect they would, though, since root has permissions to do anything. -- Mark E. Hamilton Orion International Technologies, Inc. Sandia National Laboratory, NM. 505-844-7666 -- http://mail.python.org/mailman/listinfo/python-list
Re: Python script produces sem_trywait: Permission denied
Mark E. Hamilton wrote: Sorry, I probably should have re-stated the problem: We're using Python 2.3.5 on AIX 5.2, and get the follow error messages from some of our code. I haven't yet tracked down exactly where it's coming from: sem_trywait: Permission denied sem_wait: Permission denied sem_post: Permission denied I'm I would be very concerned about these. Permission denied is somewhat baffling to me. man sem_wait on Linux doesn't show EPERM as a possible error condition. The code that likely generates these messages is in Python/thread_pthread.h near line 319. Do you have lots of threads? Do you make heavy use of semaphores? Maybe they are running out or something. Do you know if your locking is really working? We don't run these scripts as root, so I can't say whether they work as root. I suspect they would, though, since root has permissions to do anything. I'm not sure. I don't know what the Permission denied really means. I wonder if there some weird compiler optimization thing going on. Not that I'm blaming the compiler, it could well be a python problem. I just don't know. Do you have any memory debugging tools that you can run python under to see if there's something weird python is doing? Valgrind should work on PPC now, but you may need to apply a patch, I'm not sure PPC support is mainline in v3. Other possibilities include purify if that works on AIX or sentinel. n -- http://mail.python.org/mailman/listinfo/python-list
Python script produces sem_trywait: Permission denied
Ive seen these messages too on AIX 5.2. It seems to come from doing an import on piped/fork processes with a python parent. (In particular import errno) I dont know the proper solution but I got rid of the messages (similar messages came up when I ran my app) by hacking Python/thread_pthread.h. Theres a CHECK_STATUS macro the does a perror if any of the sem_* functions dont return an acceptable status. I just commented out the perror (didnt seem to hurt the python tests or my app) but I hope that someone more knowledgeable about Python internals might tell me if a more serious problem is looming. --- warren. -- http://mail.python.org/mailman/listinfo/python-list
