Can't uv add netifaces (but after uv pip install netifaces it works)

[romaia]

Using uv version 0.4.9 on linux, I cant uv add netifaces, but if I install it with uv pip install netifaces before hand, it works.

Steps to reproduce. On a new project:

uv init
uv add netifaces

results in:

Using Python 3.10.14
Creating virtualenv at: .venv
Resolved 2 packages in 1ms
error: Failed to prepare distributions
  Caused by: Failed to fetch wheel: netifaces==0.11.0
  Caused by: Build backend failed to build wheel through `build_wheel()` with exit status: 1
--- stdout:
running bdist_wheel
running build
running build_ext
checking for getifaddrs...not found. (cached)
checking for getnameinfo...not found. (cached)
checking for socket IOCTLs...not found. (cached)
checking for optional header files...none found. (cached)
checking whether struct sockaddr has a length field...no. (cached)
checking which sockaddr_xxx structs are defined...none! (cached)
checking for routing socket support...no. (cached)
checking for sysctl(CTL_NET...) support...no. (cached)
checking for netlink support...no. (cached)
building 'netifaces' extension
clang -pthread -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -fPIC -fPIC -DNETIFACES_VERSION=0.11.0 -I/home/romaia/.cache/uv/builds-v0/.tmpbYhrAX/include -I/home/romaia/.local/share/uv/python/cpython-3.10.14-linux-x86_64-gnu/include/python3.10 -c netifaces.c -o build/temp.linux-x86_64-cpython-310/netifaces.o
--- stderr:
netifaces.c:210:6: error: You need to add code for your platform.
  210 | #    error You need to add code for your platform.
      |      ^
netifaces.c:1469:22: warning: unused variable 'defaults' [-Wunused-variable]
 1469 |   PyObject *result, *defaults;
      |                      ^~~~~~~~
1 warning and 1 error generated.
error: command '/usr/bin/clang' failed with exit code 1

but if I run:

uv pip install netifaces
Resolved 1 package in 1ms
Installed 1 package in 0.61ms
 + netifaces==0.11.0

It install successfully, and after that, uv add works:

uv add netifaces
Resolved 2 packages in 2ms
Audited 1 package in 0.01ms

I am not sure if its a problem with netifaces itself, but since uv pip works, seems like a issue with uv add

[charliermarsh]

For whatever reason, that uv pip install netifaces is not building the package. It must've already been built and cached by the time you ran that command (otherwise, we'd see Prepared 1 package in...). So I suspect something else is going on here...?

[romaia]

Indeed, testing on 3 fresh vms (ubuntu 24/22/20), the problem does not happen, so I guess something in my current setup is kinda of broken.

Will try to dig deeper to find out what.

[bluss]

netifaces has wheels for python 3.8 (all platforms?) and 3.9 (not all platforms)? And no pre-built wheels available for newer pythons (>=3.10). So python version will be important for what happens there. You can use a strength of uv - easy to switch python version - configure python 3.8 for the project and that should work well for netifaces - judging from the wheel list on PyPI (See the download files view).