René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Error loading fonts on OSX 10.11","articleBody":"A colleague ran into the following error after installing a fresh copy of Matplotlib on OSX 10.11:\n\n```\n$ python -c 'import matplotlib.pyplot'\nTraceback (most recent call last):\n  File \"\u003cstring\u003e\", line 1, in \u003cmodule\u003e\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/pyplot.py\", line 29, in \u003cmodule\u003e\n    import matplotlib.colorbar\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/colorbar.py\", line 34, in \u003cmodule\u003e\n    import matplotlib.collections as collections\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/collections.py\", line 27, in \u003cmodule\u003e\n    import matplotlib.backend_bases as backend_bases\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/backend_bases.py\", line 62, in \u003cmodule\u003e\n    import matplotlib.textpath as textpath\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/textpath.py\", line 15, in \u003cmodule\u003e\n    import matplotlib.font_manager as font_manager\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/font_manager.py\", line 1420, in \u003cmodule\u003e\n    _rebuild()\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/font_manager.py\", line 1405, in _rebuild\n    fontManager = FontManager()\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/font_manager.py\", line 1043, in __init__\n    self.ttffiles = findSystemFonts(paths) + findSystemFonts()\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/font_manager.py\", line 323, in findSystemFonts\n    for f in get_fontconfig_fonts(fontext):\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/font_manager.py\", line 275, in get_fontconfig_fonts\n    stderr=subprocess.PIPE)\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py\", line 710, in __init__\n    errread, errwrite)\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py\", line 1334, in _execute_child\n    child_exception = pickle.loads(data)\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.py\", line 1382, in loads\n    return Unpickler(file).load()\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.py\", line 858, in load\n    dispatch[key](self)\n  File \"/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.py\", line 966, in load_string\n    raise ValueError, \"insecure string pickle\"\nValueError: insecure string pickle\n```\n\nNot surprisingly, the problem turns out to be in `get_fontconfig_fonts` where the command  `subprocess.Popen(['fc-list', '--format=%{file}\\\\n'], ...)` returns a `ValueError` instead of the expected `OSError, IOError` and so the routine tries to load a pickle from the error message text and fails.  `fc-list` does not exist on my colleague's system.\n","author":{"url":"https://github.com/matthew-brett","@type":"Person","name":"matthew-brett"},"datePublished":"2015-11-03T01:28:55.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":22},"url":"https://github.com/5386/matplotlib/issues/5386"}