Error with pylibmc on Mac OS Lion

Question

I have a problem with pylibmc on Mac OS Lion.

libmemcached — 1.0.4

pylibmc — 1.2.3

$ python
Python 2.7.1 (r271:86832, Jun 25 2011, 05:09:01) 
[GCC 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.15.00)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import pylibmc
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Library/Python/2.7/site-packages/pylibmc/__init__.py", line 70, in <module>
    import _pylibmc
ImportError: dlopen(/Library/Python/2.7/site-packages/_pylibmc.so, 2): Symbol not found: _memcached_add
  Referenced from: /Library/Python/2.7/site-packages/_pylibmc.so
  Expected in: flat namespace
 in /Library/Python/2.7/site-packages/_pylibmc.so

But it works with sudo!

$ sudo python
Password:
Python 2.7.1 (r271:86832, Jun 25 2011, 05:09:01) 
[GCC 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.15.00)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import pylibmc
>>> 

Any ideas?

Answer 1

Installation in 32-bit mode solved the problem.

1. You need to install libevent in 32-bit mode

    brew install --universal libevent 

2. Next to download libmemcached source (1.0.8 version works for me) and configure force for 32 bit arch:

    ./configure --build=i386-apple-darwin11.4.2 "CFLAGS=-m32" "CXXFLAGS=-m32" "LDFLAGS=-m32" make sudo make install 

   where 11.4.2 is the version of kernel

3. Reinstall pylibmc

    sudo pip uninstall pylibmc sudo pip install pylibmc 

4. Now it works

    $ python -c 'import pylibmc' $ 

Answer 2

Looks like a build and/or installation problem with libmemcached. Maybe you can check out issue #101? https://github.com/lericson/pylibmc/issues/101

Answer 3

I have similar issue.

I am running macOS with apple silicon. running python 3.7 with x86 interpreter.

after installing libmemcached with brew install libmemcached I was able to install pylibmc with the following command: pip install pylibmc==1.6.0 --install-option="--with-libmemcached=/opt/homebrew/Cellar/libmemcached/1.0.18_2"

but while trying to import pylibmc it failed with: ImportError: dlopen(.../site-packages/_pylibmc.cpython-37m-darwin.so, 0x0002): symbol not found in flat namespace '_memcached_add'

I am thing that brew install compiling the library with apple silicon but then i am trying to use it with x86 interpreter. Any suggestions ?