Re: Pkgsrc python cannot import SemLock on CentOS

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

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)