[Distutils] Potential issue with multiple easy_install instances and single easy_install.pth

[Phillip J. Eby]

At 07:14 PM 10/18/2008 -0700, Garrett Cooper (garrcoop) wrote:
>Hi Python folks,
>         As part of a build system I work with, my group installs
>multiple Python packages via source using easy_install. One such issue
>I've seen before in the past is that when using multiple easy_install
>instances (via multiple make jobs), the last instance that opened up
>easy_install.pth records its changes; the file should contain entries
>for all packages installed by easy_install.

easy_install doesn't support simultaneous parallel installations to 
the same target directory, and there are no plans at the moment to 
add that support.

Note, however, that if you use the -m (--multi-version) option, then 
easy_install will  not save the .pth file unless there was already a 
default version of the target package present.  However, if you begin 
by deleting the .pth file altogether, then using -m will avoid 
creating or updating it.

Of course, the downside of -m is that you will not be able to access 
the installed packages except via setuptools-built scripts or by 
using explicit require() calls.