[package] boost/all-versions: Fails to install attempting to write to C:\\.conan

Package and Environment Details

• Package Name/Version: boost/1.73
• Operating System+version: Windows 10 x64
• Compiler+version: Visual Studio 2017/2019
• Conan version: conan 1.26.0

Conan profile

C:\dev\test\build>conan profile show default
Configuration for profile default:

[settings]
os=Windows
os_build=Windows
arch=x86_64
arch_build=x86_64
compiler=Visual Studio
compiler.version=16
build_type=Release
[options]
[build_requires]
[env]

Steps to reproduce

I’ve just tried to run the most basic use-case and it has failed! I’ve installed conan using the Windows installer: conan-win-64_1_26_0.exe onto my Windows 10 dev machine as an administrator (not per-user), created a directory with the following into the C:\dev\test\conanfile.txt:

[requires]
boost/1.73.0

[generators]
cmake_find_package
cmake_paths

I’ve had success installing other packages, though:

• nlohmann_json/3.8.0
• zlib/1.2.11
• fmt/6.2.0
• libpng/1.6.37
• spdlog/1.6.1

Also fails on boost/1.69.0.

Note also that this PC is domain joined, and I don’t have write access to the root of C:\ drive.

Logs

Click to expand log

PS C:\dev\test\build> conan install ..
Auto detecting your dev setup to initialize the default profile (C:\Users\<myusername>\.conan\profiles\default)
Found Visual Studio 16
Default settings
        os=Windows
        os_build=Windows
        arch=x86_64
        arch_build=x86_64
        compiler=Visual Studio
        compiler.version=16
        build_type=Release
*** You can change them in C:\Users\<myusername>\.conan\profiles\default ***
*** Or override with -s compiler='other' -s ...s***


WARN: Remotes registry file missing, creating default one in C:\Users\<myusername>\.conan\remotes.json
Configuration:
[settings]
arch=x86_64
arch_build=x86_64
build_type=Release
compiler=Visual Studio
compiler.runtime=MD
compiler.version=16
os=Windows
os_build=Windows
[options]
[build_requires]
[env]

boost/1.73.0: Not found in local cache, looking in remotes...
boost/1.73.0: Trying with 'conan-center'...
Downloading conanmanifest.txt completed [1.26k]
Downloading conanfile.py completed [40.72k]
Downloading conan_export.tgz completed [0.36k]
Decompressing conan_export.tgz completed [0.00k]
boost/1.73.0: Downloaded recipe revision 0
zlib/1.2.11: Not found in local cache, looking in remotes...
zlib/1.2.11: Trying with 'conan-center'...
Downloading conanmanifest.txt completed [0.31k]
Downloading conanfile.py completed [7.88k]
Downloading conan_export.tgz completed [0.31k]
Decompressing conan_export.tgz completed [0.00k]
zlib/1.2.11: Downloaded recipe revision 0
bzip2/1.0.8: Not found in local cache, looking in remotes...
bzip2/1.0.8: Trying with 'conan-center'...
Downloading conanmanifest.txt completed [0.17k]
Downloading conanfile.py completed [2.07k]
Downloading conan_export.tgz completed [0.24k]
Decompressing conan_export.tgz completed [0.00k]
bzip2/1.0.8: Downloaded recipe revision 0
Traceback (most recent call last):
  File "conan\conans\client\command.py", line 2035, in run
  File "conan\conans\client\command.py", line 506, in install
  File "conan\conans\client\conan_api.py", line 92, in wrapper
  File "conan\conans\client\conan_api.py", line 578, in install
  File "conan\conans\client\manager.py", line 56, in deps_install
  File "conan\conans\client\graph\graph_manager.py", line 109, in load_graph
  File "conan\conans\client\graph\graph_manager.py", line 236, in _resolve_graph
  File "conan\conans\client\graph\graph_manager.py", line 346, in _load_graph
  File "conan\conans\client\graph\graph_manager.py", line 277, in _recurse_build_requires
  File "conan\conans\client\graph\graph_binaries.py", line 343, in evaluate_graph
  File "conan\conans\client\graph\graph_binaries.py", line 167, in _evaluate_node
  File "conan\conans\client\graph\graph_binaries.py", line 208, in _process_node
  File "conan\conans\paths\package_layouts\package_cache_layout.py", line 31, in wrap
  File "conan\conans\util\windows.py", line 82, in path_shortener
  File "conan\conans\util\files.py", line 275, in mkdir
  File "os.py", line 220, in makedirs
PermissionError: [WinError 5] Access is denied: 'C:\\.conan'

[Croydon]

I think that some paths may become so long that it is reasonable to assume that it exceeds the path limit on Windows for everyone, hence setting this attribute that it works out of the box for people

[uilianries]

@shoreadmin Thanks for your feedback!

You can disable short_paths, or change the base path if you want: https://docs.conan.io/en/latest/reference/env_vars.html#conan-user-home-short

The main reason for using C:\ is because on Windows file paths can have 256 characters at least. However, you can change the default behavior on Windows: https://docs.conan.io/en/latest/reference/conanfile/attributes.html#short-paths-reference

Regards!