Import error on MacOS

[joejacobs]

Importing libvlc doesn't work on MacOS. When I try to import VLC (using VLC 3.0 RC9) I get the following error:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/user/miniconda/envs/blah/lib/python3.6/site-packages/vlc.py", line 198, in <module>
    dll, plugin_path  = find_lib()
  File "/Users/user/miniconda/envs/blah/lib/python3.6/site-packages/vlc.py", line 183, in find_lib
    dll = ctypes.CDLL(p)
  File "/Users/user/miniconda/envs/blah/lib/python3.6/ctypes/__init__.py", line 348, in __init__
    self._handle = _dlopen(self._name, mode)
OSError: dlopen(/Applications/VLC.app/Contents/MacOS/lib/libvlc.dylib, 6): Library not loaded: @rpath/libvlccore.dylib
  Referenced from: /Applications/VLC.app/Contents/MacOS/lib/libvlc.dylib
  Reason: image not found

It looks like libvlccore.dylib needs to be imported first before importing libvlc.dylib.

[oaubert]

I do not have a Mac at hand to test this, but I would tend to say that this dynamic linker issue should be reported to upstream VLC. I used to solve such issues with install_name_tool some years ago.
Maybe @mrJean1 (who develops on Mac) can give some hints?

[mrJean1]

Where can I find VLC 3.0 RC9? What is environment variable [DY]LD_LIBRARY_PATH set to?

There is no problem with VLC 2.2.8 and python-vlc/generated/3.0/vlc.py using Python 2.7.14 and 3.6.4 on macOS 10.13.3 High Sierra.

Btw, if VLC 3+ does load multiple *.dylib's, perhaps [DY]LD_LIBRARY_PATH should be set, e.g. to the directory where libvlc.dlib is found?

[mrJean1]

Using this VLC 3.0 RC9 build, the error is the same (for Python 2.7.14 and 3.6.4):

% python vlc.py 
Traceback (most recent call last):
  File "vlc.py", line 198, in <module>
    dll, plugin_path  = find_lib()
  File "vlc.py", line 183, in find_lib
    dll = ctypes.CDLL(p)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/ctypes/__init__.py", line 366, in __init__
    self._handle = _dlopen(self._name, mode)
OSError: dlopen(/Applications/VLC.app/Contents/MacOS/lib/libvlc.dylib, 6): Library not loaded: @rpath/libvlccore.dylib
  Referenced from: /Applications/VLC.app/Contents/MacOS/lib/libvlc.dylib
  Reason: image not found

Both .dylib's are there and the VLC 3.0 RC9 App works just fine. It Looks like an issue with the libvlc.dylib. Does the VLC App even load that libvlc.dylib?

% ls -al /Applications/VLC.app/Contents/MacOS/lib/
total 2680
drwxr-xr-x@ 6 jean  admin      204 Feb  5 23:11 .
drwxr-xr-x@ 7 jean  admin      238 Feb  5 23:11 ..
-rwxr-xr-x@ 1 jean  admin   180276 Feb  5 23:11 libvlc.5.dylib
lrwxr-xr-x  1 jean  admin       14 Feb  5 23:11 libvlc.dylib -> libvlc.5.dylib
-rwxr-xr-x@ 1 jean  admin  1179516 Feb  5 23:11 libvlccore.9.dylib
lrwxr-xr-x  1 jean  admin       18 Feb  5 23:11 libvlccore.dylib -> libvlccore.9.dylib

% ls -al /Applications/VLC2.2.8.app/Contents/MacOS/lib/
total 2200
drwxr-xr-x@ 6 jean  admin     204 Nov 22 17:06 .
drwxr-xr-x@ 8 jean  admin     272 Nov 22 17:06 ..
-rw-r--r--@ 1 jean  admin  124256 Nov 22 17:06 libvlc.5.dylib
lrwxr-xr-x  1 jean  admin      14 Nov 22 17:06 libvlc.dylib -> libvlc.5.dylib
-rw-r--r--@ 1 jean  admin  989104 Nov 22 17:06 libvlccore.8.dylib
lrwxr-xr-x  1 jean  admin      18 Nov 22 17:06 libvlccore.dylib -> libvlccore.8.dylib

However, the following command line does not show the error:

% env DYLD_LIBRARY_PATH=/Applications/VLC.app/Contents/MacOS/lib/ python vlc.py
Usage: vlc.py [options] <movie_filename>
Once launched, type ? for help.

Build date: Thu Jan  4 23:45:25 2018 3.0.0 (0x3006500)
LibVLC version: 3.0.0-rc9 Vetinari (0x0)
LibVLC compiler: clang: warning: argument unused during compilation: '-mmacosx-version-min=10.7' [-Wunused-command-line-argument]
Plugin path: /Applications/VLC.app/Contents/MacOS/plugins

Modifying vlc.py as follows does not solve the problem:

    ....
    elif sys.platform.startswith('darwin'):
        # FIXME: should find a means to configure path
        d = '/Applications/VLC.app/Contents/MacOS/'
        e = 'DYLD_LIBRARY_PATH'
        if e in os.environ:
             os.environ[e] = d + 'lib:' + os.environ[e]
        else:
             os.environ[e] = d + 'lib'
        p = d + 'lib/libvlc.dylib'
        ....

Neither does setting PYTHON_VLC_LIB_PATH and PYTHON_VLC_MODULE_PATH.

But changing vlc.py as follows does work:

    ....
    elif sys.platform.startswith('darwin'):
        # FIXME: should find a means to configure path
        d = '/Applications/VLC.app/Contents/MacOS/'
        p = d + 'lib/libvlc.dylib'
        if os.path.exists(p):
            # force pre-load of libvlccore.dylib  # ****
            ctypes.CDLL(d + 'lib/libvlccore.dylib')  # ****
            dll = ctypes.CDLL(p)
            for p in ('modules', 'plugins'):
                ...

[oaubert]

Great work Jean. Could you submit a patch with this modification (so that authorship is preserved)?

[mrJean1]

Will do. But why is this an suddenly an issue? Does it only happen with the macOS version of VLC? /Jean

…

On Feb 14, 2018, at 11:01 AM, Olivier Aubert ***@***.***> wrote: Great work Jean. Could you submit a patch with this modification (so that authorship is preserved)? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.

[oaubert]

Something must have changed in the macosx build chain. The extras/package/macosx directory of VLC has had lots of changes these last months. I would even expect that videolan/vlc@f6e51b0 (and the following one removing build-package.sh) look like the ones that could have introduced the issue.

[mrJean1]

Submitted patch for the header.py file. /Jean

…

On Feb 14, 2018, at 11:59 AM, Olivier Aubert ***@***.***> wrote: Something must have changed in the macosx build chain. The extras/package/macosx directory of VLC has had lots of changes these last months. I would even expect that ***@***.*** (and the following one removing build-package.sh) look like the ones that could have introduced the issue. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.

[oaubert]

I don't see the patch. Where did you submit it?

[mrJean1]

Not sure what happened. Redid the patch and it should be there now as mrJean1-patch-1. /Jean

…

On Feb 16, 2018, at 4:12 AM, Olivier Aubert ***@***.***> wrote: I don't see the patch. Where did you submit it? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#37 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AVIMYZTZJd1hi4bWdYsf7hIKdxNbClwgks5tVUZ_gaJpZM4R4OBL>.

[smilemcm]

in my case, there is no C library in my system..
so I installed the vlc application through apple store.
in my case application directory is "/Applications/VLC 2.app/Contents/MacOS/lib"
so i open vlc.py file in python lib,
I change the directory name like below

  # elif sys.platform.startswith('darwin'):
        # FIXME: should find a means to configure path
        #d = '/Applications/VLC.app/Contents/MacOS/'.        <- origin directory name
       d = '/Applications/VLC 2.app/Contents/MacOS/'.        <- my system directory
        c = d + 'lib/libvlccore.dylib'
        p = d + 'lib/libvlc.dylib'
        if os.path.exists(p) and os.path.exists(c):
            # pre-load libvlccore VLC 2.2.8+
            ctypes.CDLL(c)
            dll = ctypes.CDLL(p)

[AccelQuasarDragon]

Just a quick note because this thread keeps popping up on my google searches:

If you are packaging with pyinstaller for Mac, VLC.app MUST be installed in the applications folder for it to work smoothly.

If VLC is not in the applications folder (for example you want your .app to work regardless if the user has previously installed VLC), you must add libvlccore.dylib and libvlc.dylib manually in the spec file, and modify vlc.py to search in the _MEIPASS folder:

adding dylibs in the .spec file

a.binaries + [
        ("libvlc.dylib", "/Users/KivySchool/CODING/BasicPyVLC/VLC.app/Contents/MacOS/lib/libvlc.dylib", "BINARY"),
        ("libvlccore.dylib", "/Users/KivySchool/CODING/BasicPyVLC/VLC.app/Contents/MacOS/lib/libvlccore.dylib", "BINARY")
        ],

vlc.py changed to look in sys._MEIPASS folder

elif sys.platform.startswith('darwin'):
    d = sys._MEIPASS
    c = os.path.join(d, "libvlccore.dylib")
    p = os.path.join(d, "libvlc.dylib")
    print("paths exists and loaded?", c, p, os.path.exists(p), os.path.exists(c))
    if os.path.exists(p) and os.path.exists(c):
        # pre-load libvlccore VLC 2.2.8+
        ctypes.CDLL(c)
        dll = ctypes.CDLL(p)
        for p in ('modules', 'plugins'):
            p = os.path.join(d, p)
            if os.path.isdir(p):
                plugin_path = p
                print("pluginpath", plugin_path, os.path.exists(plugin_path))
                break