pip 1.5.6 on Linux 3.13.0-32-generic Ubuntu 14.04 Python 2.7.6, when several factors increase download URL length, fails with an "IOError: [Errno 36] File name too long" in the download cache, because ...
# pip Traceback (most recent call last): File "/usr/bin/pip", line 11, in <module> load_entry_point('pip==20.0.2', 'console_scripts', 'pip')() File "/usr/lib/python3 ...