virtualEnvironment/lib/python2.7/site-packages/pip/locations.py
def _get_build_prefix():
    """ Returns a safe build_prefix """
    path = os.path.join(
        tempfile.gettempdir(),
        'pip_build_%s' % __get_username().replace(' ', '_')
    )
    if WINDOWS:
        """ on windows(tested on 7) temp dirs are isolated """
        return path
    try:
        os.mkdir(path)
        write_delete_marker_file(path)
    except OSError:
        file_uid = None
        try:
            # raises OSError for symlinks
            # https://github.com/pypa/pip/pull/935#discussion_r5307003
            file_uid = get_path_uid(path)
        except OSError:
            file_uid = None

        if file_uid != os.geteuid():
            msg = (
                "The temporary folder for building (%s) is either not owned by"
                " you, or is a symlink." % path
            )
            print(msg)
            print(
                "pip will not work until the temporary folder is either "
                "deleted or is a real directory owned by your user account."
            )
            raise exceptions.InstallationError(msg)
    return path
def _get_build_prefix():
    """ Returns a safe build_prefix """
    path = os.path.join(
        tempfile.gettempdir(),
        'pip_build_%s' % __get_username().replace(' ', '_')
    )
    if WINDOWS:
        """ on windows(tested on 7) temp dirs are isolated """
        return path
    try:
        os.mkdir(path)
        write_delete_marker_file(path)
    except OSError:
        file_uid = None
        try:
            # raises OSError for symlinks
            # https://github.com/pypa/pip/pull/935#discussion_r5307003
            file_uid = get_path_uid(path)
        except OSError:
            file_uid = None

        if file_uid != os.geteuid():
            msg = (
                "The temporary folder for building (%s) is either not owned by"
                " you, or is a symlink." % path
            )
            print(msg)
            print(
                "pip will not work until the temporary folder is either "
                "deleted or is a real directory owned by your user account."
            )
            raise exceptions.InstallationError(msg)
    return path
Returns a safe build_prefix