Problem running Virtualenv on Mac OS X

Question

I'm using virtualenv-1.4.5 on Mac OS X 10.6.2 (Xcode is installed) and Python 2.6. Here's what I get when I attempt to run a virtualenv...

 Mac-Pro:pylonsdev paul$ virtualenv --no-site-packages -v trythis
Creating trythis/lib/python2.6
Symlinking Python bootstrap modules
  Symlinking trythis/lib/python2.6/_abcoll.pyc
  Symlinking trythis/lib/python2.6/_abcoll.pyo
  Symlinking trythis/lib/python2.6/abc.pyc
  Symlinking trythis/lib/python2.6/abc.pyo
  Symlinking trythis/lib/python2.6/codecs.pyc
  Symlinking trythis/lib/python2.6/codecs.pyo
  Symlinking trythis/lib/python2.6/config
  Symlinking trythis/lib/python2.6/copy_reg.pyc
  Symlinking trythis/lib/python2.6/copy_reg.pyo
  Symlinking trythis/lib/python2.6/encodings
  Symlinking trythis/lib/python2.6/fnmatch.pyc
  Symlinking trythis/lib/python2.6/fnmatch.pyo
  Symlinking trythis/lib/python2.6/genericpath.pyc
  Symlinking trythis/lib/python2.6/genericpath.pyo
  Symlinking trythis/lib/python2.6/lib-dynload
  Symlinking trythis/lib/python2.6/linecache.pyc
  Symlinking trythis/lib/python2.6/linecache.pyo
  Symlinking trythis/lib/python2.6/locale.pyc
  Symlinking trythis/lib/python2.6/locale.pyo
  Symlinking trythis/lib/python2.6/ntpath.pyc
  Symlinking trythis/lib/python2.6/ntpath.pyo
  Symlinking trythis/lib/python2.6/os.pyc
  Symlinking trythis/lib/python2.6/os.pyo
  Symlinking trythis/lib/python2.6/posixpath.pyc
  Symlinking trythis/lib/python2.6/posixpath.pyo
  Symlinking trythis/lib/python2.6/re.pyc
  Symlinking trythis/lib/python2.6/re.pyo
  Symlinking trythis/lib/python2.6/sre.pyc
  Symlinking trythis/lib/python2.6/sre.pyo
  Symlinking trythis/lib/python2.6/sre_compile.pyc
  Symlinking trythis/lib/python2.6/sre_compile.pyo
  Symlinking trythis/lib/python2.6/sre_constants.pyc
  Symlinking trythis/lib/python2.6/sre_constants.pyo
  Symlinking trythis/lib/python2.6/sre_parse.pyc
  Symlinking trythis/lib/python2.6/sre_parse.pyo
  Symlinking trythis/lib/python2.6/stat.pyc
  Symlinking trythis/lib/python2.6/stat.pyo
  Symlinking trythis/lib/python2.6/types.pyc
  Symlinking trythis/lib/python2.6/types.pyo
  Symlinking trythis/lib/python2.6/UserDict.pyc
  Symlinking trythis/lib/python2.6/UserDict.pyo
  Symlinking trythis/lib/python2.6/warnings.pyc
  Symlinking trythis/lib/python2.6/warnings.pyo
Creating trythis/lib/python2.6/site-packages
Writing trythis/lib/python2.6/site.py
Writing trythis/lib/python2.6/orig-prefix.txt
Writing trythis/lib/python2.6/no-global-site-packages.txt
Creating parent directories for trythis/include
Symlinking trythis/include/python2.6
Creating trythis/bin
New python executable in trythis/bin/python
Changed mode of trythis/bin/python to 0755
Symlinking trythis/.Python
Error [Errno 2] No such file or directory while executing command install_name_tool -change /System/Library/Frameworks/Pyt...ython @executable_path/../.Python trythis/bin/python
Could not call install_name_tool -- you must have Apple's development tools installed
Traceback (most recent call last):
  File "/usr/local/bin/virtualenv", line 8, in <module>
    load_entry_point('virtualenv==1.4.5', 'console_scripts', 'virtualenv')()
  File "/Library/Python/2.6/site-packages/virtualenv-1.4.5-py2.6.egg/virtualenv.py", line 529, in main
    use_distribute=options.use_distribute)
  File "/Library/Python/2.6/site-packages/virtualenv-1.4.5-py2.6.egg/virtualenv.py", line 612, in create_environment
    site_packages=site_packages, clear=clear))
  File "/Library/Python/2.6/site-packages/virtualenv-1.4.5-py2.6.egg/virtualenv.py", line 806, in install_python
    py_executable])
  File "/Library/Python/2.6/site-packages/virtualenv-1.4.5-py2.6.egg/virtualenv.py", line 557, in call_subprocess
    cwd=cwd, env=env)
  File "/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/subprocess.py", line 595, in __init__
  File "/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/subprocess.py", line 1106, in _execute_child
OSError: [Errno 2] No such file or directory

Any suggestions why this error is being thrown?

Answer 1

Well, the error message includes this:

you must have Apple's development tools installed

Do you? They're on the separate XCode disk that came with OSX.

Answer 2

There's also a bug with virtualenv on 10.6 See the ticket on virtualenv's bitbucket. Even if you solve the problem you're having you'll still run into another problem (I think image not found for Python.framework, but I don't remember - I didn't take any notes when I ran into this)

I did some investigating into this and I hope the root of the problem with be resolved with Python 2.7 - certainly people know about it, and submitted a patch to CPython to fix it.

However, it does seem like some people have had good results with 10.6.2 and virtualenv 1.4.5... or not using the system Python anymore (macports, build-by-hand).