5.0 KiB
Gems, Eggs and Perl Modules
On a fresh macOS installation there are three empty directories for add-ons available to all users:
/Library/Ruby
/Library/Python
/Library/Perl
Starting with OS X Lion (10.7), you need sudo to install to these like
so: sudo gem install, sudo easy_install or sudo cpan -i.
An option to avoid sudo is to use an access control list:
chmod +a 'user:YOUR_NAME_HERE allow add_subdirectory,add_file,delete_child,directory_inherit' /Library/Python/2.7/site-packages,
for example, will let you add packages to Python 2.7 as yourself. That
is probably safer than changing the group ownership of the directory.
So why was I using sudo?
Habit maybe?
One reason is executables go in /usr/local/bin. Usually this isn’t a
writable location. But if you installed Homebrew as we recommend,
/usr/local will be writable without sudo. So now you are good to
install the development tools you need without risking a sudo.
Python packages (eggs) without sudo
Rather than changing the rights on /Library/Python, we recommend the following options:
With a brewed Python - you don’t need sudo
Note, easy_install is deprecated. We install pip (or pip3 for
python3) along with python/python3.
We set up distutils such that pip install will always put modules in
$(brew --prefix)/lib/pythonX.Y/site-packages and scripts in
$(brew --prefix)/share/python. Therefore, you won’t need sudo!
Do brew info python or brew info python3 for precise information
about the paths. Note, a brewed Python still searches for modules in
/Library/Python/X.Y/site-packages and also in
~/Library/Python/X.Y/lib/python/site-packages.
With system’s Python
This is only recommended if you don't use a brewed Python.
On macOS, any Python version X.Y also searches in
~/Library/Python/X.Y/lib/python/site-packages for
modules.
That dir might not yet exist, but you can create it:
mkdir -p ~/Library/Python/2.7/lib/python/site-packages
To teach easy_install and pip to install there, either use the
—user switch or create a ~/.pydistutils.cfg file with the
following content:
[install]
install_lib = ~/Library/Python/$py_version_short/lib/python/site-packages
Using virtualenv - works with brewed and system’s Python
Virtualenv ships pip and
creates isolated Python environments with separate site-packages,
therefore you won’t need sudo.
Rubygems without sudo
If you use rbenv or RVM then you should ignore this stuff
Brewed Ruby installs executables to $(brew --prefix)/opt/ruby/bin
without sudo. You should add this to your path. See the caveats in the
ruby formula for up-to-date information.
With system’s Ruby
To make Ruby install to /usr/local, we need to add
gem: -n/usr/local/bin to your ~/.gemrc. It’s YAML…so do it manually
or use this:
echo "gem: -n/usr/local/bin" >> ~/.gemrc
However all versions of RubyGems before 1.3.6 are buggy and ignore the above setting. Sadly a fresh install of Snow Leopard comes with 1.3.5. Currently the only known way to get round this is to upgrade rubygems as root:
sudo gem update --system
An Alternative
Just install everything into the Homebrew prefix like this:
echo "export GEM_HOME=\"$(brew --prefix)\"" >> ~/.bashrc
It doesn’t work! I get some “permissions” error when I try to install stuff!
Note, maybe you shouldn’t do this on Lion, since Apple have decided it is not a good default.
If you ever did a sudo gem, etc. before then a lot of files will have
been created chown root. Fix with:
sudo chown -R $USER /Library/Ruby /Library/Perl /Library/Python
Perl CPAN Modules without sudo
The Perl module local::lib works similarly to rbenv/RVM (although for modules only, not perl installations). A simple solution that only pollutes your /Library/Perl a little is to install local::lib with sudo:
sudo cpan local::lib
Note that will install some other dependencies like Module::Install.
Then put the appropriate incantation in your shell’s startup, e.g. for
.bash_profile you insert the below, for others see the
local::lib docs.
eval $(perl -I$HOME/perl5/lib/perl5 -Mlocal::lib)
Now (after you restart your shell) cpan or perl -MCPAN -eshell etc.
will install modules and binaries in ~/perl5 and the relevant
subdirectories will be in your PATH and PERL5LIB etc.
Avoiding sudo altogether for Perl
If you don’t even want (or can’t) use sudo for bootstrapping
local::lib just manually install local::lib in
~/perl5 and add the relevant path to PERL5LIB before the .bashrc eval incantation.
Another alternative is to use perlbrew to install a separate copy of Perl in your home directory, or wherever you like :
curl -kL http://install.perlbrew.pl | bash
perlbrew install perl-5.16.2
echo ".~/perl5/perlbrew/etc/bashrc" >> ~/.bashrc