如果pip install-r requirements.txt被中断，是否会删除已经安装的软件包？

Question

While in the virtual environment, if pip install -r requirements.txt gets interrupted, will the packages that have been already installed get deleted?

I use the

pip3 install -r requirements.txt

You see from the snapshot, I have installed openstacksdk , Pillow , pycparser , when I install the PyMYSQL I get the interrupt.

but in my venv/lib/python3.5/site-packages there is none of openstacksdk , Pillow , pycparser :

If it did not delete them, where did the packages get installed?

Answer 1

You should take a look of the pip install steps.

the packages you see in the site-packages is the wheels.

there are main two steps of pip install packages:

1. Collecting packages.

2. Build wheels for collected packages.

After Built wheels, then there are packages in the site-packages . your pip install interrupted in the first step, so there did not reach the second step.