Re: Pkgsrc python cannot import SemLock on CentOS

[Jason Bacon <outpaddling%yahoo.com@localhost>]

Note to posterity...

This problem seems to have solved itself.?? In the latest pkgsrc-current 
with python 3.7,
import multiprocessing" now works fine.

Cheers,

?????? JB

On 2018-11-06 17:48, Jason Bacon wrote:
> Yes, it's mounted and writable.?? I've read numerous threads about this 
> issue and that's
> a common suggestion.
>
> Note in the original message that Yum's python does not exhibit the 
> issue.?? It must be something
> specific to the pkgsrc build.
>
> Linux centosdev.ceas?? bacon ~ 1004: ls /dev/shm/
> Linux centosdev.ceas?? bacon ~ 1005: touch /dev/shm/temp
> Linux centosdev.ceas?? bacon ~ 1006: ls /dev/shm/
> temp
> Linux centosdev.ceas?? bacon ~ 1007: rm /dev/shm/temp
>
> Thanks,
>
> ?????? JB
>
> On 11/6/18 4:44 PM, Adam wrote:
> > Is /dev/shm mounted?
> >
> > How about Python 3.7.1?
> >
> > Adam
> >
> >
> > > Anyone know how to get around this? It's hit me a couple of times 
> > > now in applications I'd really
> > > like to deploy via pkgsrc.
> > >
> > > Yum's python imports fine, but I've seen this issue with multiple 
> > > versions of pkgsrc python.
> > >
> > > It's not true that the platform lacks a functioning sem_open().
> > >
> > > Thanks,
> > >
> > > ???????? JB
> > >
> > > Pkgsrc python:
> > >
> > > Linux centosdev.ceas?? bacon ~ 1019: python3.7
> > > Python 3.7.0 (default, Oct 15 2018, 04:47:22)
> > > [GCC 6.4.0] on linux
> > > Type "help", "copyright", "credits" or "license" for more information.
> > > > > > import multiprocessing
> > > > > > from multiprocessing import synchronize
> > > Traceback (most recent call last):
> > > ???? File "/usr/pkg/lib/python3.7/multiprocessing/synchronize.py", 
> > > line 29, in <module>
> > > ???????? from _multiprocessing import SemLock, sem_unlink
> > > ImportError: cannot import name 'SemLock' from '_multiprocessing' 
> > > (/usr/pkg/lib/python3.7/lib-dynload/_multiprocessing.so)
> > >
> > > During handling of the above exception, another exception occurred:
> > >
> > > Traceback (most recent call last):
> > > ???? File "<stdin>", line 1, in <module>
> > > ???? File "/usr/pkg/lib/python3.7/multiprocessing/synchronize.py", 
> > > line 33, in <module>
> > > ???????? " synchronization primitives needed will not" +
> > > ImportError: This platform lacks a functioning sem_open 
> > > implementation, therefore, the required synchronization primitives 
> > > needed will not function, see issue 3770.
> > > Yum python:
> > >
> > > Linux centosdev.ceas?? bacon ~ 1019: /usr/bin/python
> > > Python 2.7.5 (default, Jul 13 2018, 13:06:57)
> > > [GCC 4.8.5 20150623 (Red Hat 4.8.5-28)] on linux2
> > > Type "help", "copyright", "credits" or "license" for more information.
> > > > > > import multiprocessing
> > > > > > from multiprocessing import synchronize
> > > Linux centosdev.ceas?? bacon ~ 1020: uname -a
> > > Linux centosdev.ceas.uwm.edu 3.10.0-693.11.1.el7.x86_64 #1 SMP Mon 
> > > Dec 4 23:52:40 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
> > > Linux centosdev.ceas?? bacon ~ 1022: cat /etc/redhat-release
> > > CentOS Linux release 7.5.1804 (Core)