无法安装Python的webview库，已装VS运行时仍报错

问题详情 #

已安装Microsoft Visual Studio运行时库，使用Python 3.10执行pip install webview时编译失败，核心报错为PATH_MAX未定义，导致C扩展编译终止。已尝试安装Microsoft Visual C++ 2015-2022 Redistributable (x86) - 14.32.31326，问题未解决。

完整报错信息 #

C:\Users\rouna>pip install webview
Collecting webview
  Using cached webview-0.1.5.tar.gz (18 kB)
  Preparing metadata (setup.py) ... done
Building wheels for collected packages: webview
  Building wheel for webview (setup.py) ... error
  error: subprocess-exited-with-error

  × python setup.py bdist_wheel did not run successfully.
  │ exit code: 1
  ╰─> [19 lines of output]
      running bdist_wheel
      running build
      running build_ext
      building 'webview' extension
      creating build
      creating build\temp.win-amd64-3.10
      creating build\temp.win-amd64-3.10\Release
      creating build\temp.win-amd64-3.10\Release\webview
      C:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Tools\MSVC\14.35.32215\bin\HostX86\x64\cl.exe /c /nologo /Ox /W3 /GL /DNDEBUG /MD -DWEBVIEW_WINAPI=1 -IC:\Users\rouna\AppData\Local\Programs\Python\Python310\include -IC:\Users\rouna\AppData\Local\Programs\Python\Python310\Include -IC:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Tools\MSVC\14.35.32215\include -IC:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Tools\MSVC\14.35.32215\ATLMFC\include -IC:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Auxiliary\VS\include -IC:\Program Files (x86)\Windows Kits\10\include\10.0.22000.0\ucrt -IC:\Program Files (x86)\Windows Kits\10\\include\10.0.22000.0\\um -IC:\Program Files (x86)\Windows Kits\10\\include\10.0.22000.0\\shared -IC:\Program Files (x86)\Windows Kits\10\\include\10.0.22000.0\\winrt -IC:\Program Files (x86)\Windows Kits\10\\include\10.0.22000.0\\cppwinrt -IC:\Program Files (x86)\Windows Kits\NETFXSDK\4.8\include\um /Tcwebview/webview.c /Fobuild\temp.win-amd64-3.10\Release\webview/webview.obj
      webview.c
      C:\Users\rouna\AppData\Local\Temp\pip-install-67e1r8x0\webview_0f6456dc97e347ebac52664734281c5e\webview\webview.h(1085): warning C4477: 'sscanf' : format string '%02x' requires an argument of type 'unsigned int *', but variadic argument 1 has type 'char *'
      C:\Users\rouna\AppData\Local\Temp\pip-install-67e1r8x0\webview_0f6456dc97e347ebac52664734281c5e\webview\webview.h(1085): note: consider using '%hhx' in the format string
      C:\Users\rouna\AppData\Local\Temp\pip-install-67e1r8x0\webview_0f6456dc97e347ebac52664734281c5e\webview\webview.h(1338): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
      webview/webview.c(117): error C2065: 'PATH_MAX': undeclared identifier
      webview/webview.c(117): error C2057: expected constant expression
      webview/webview.c(117): error C2466: cannot allocate an array of constant size 0
      webview/webview.c(117): error C2133: 'result': unknown size
      webview/webview.c(123): warning C4034: sizeof returns 0
      error: command 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2022\\BuildTools\\VC\\Tools\\MSVC\\14.35.32215\\bin\\HostX86\\x64\\cl.exe' failed with exit code 2
      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
  ERROR: Failed building wheel for webview
  Running setup.py clean for webview
Failed to build webview
ERROR: Could not build wheels for webview, which is required to install pyproject.toml-based projects

解决方法 #

方法1：安装完整的Visual Studio Build Tools组件 #

只安装运行时库无法满足编译C扩展的需求，需要安装包含Windows SDK的完整Build Tools：

• 打开Visual Studio Installer，选择「使用C++的桌面开发」工作负载
• 确保勾选对应系统版本的「Windows 10 SDK」或「Windows 11 SDK」
• 安装完成后重启命令行窗口，重新执行pip install webview

方法2：手动指定PATH_MAX宏定义临时解决 #

如果不想重装Build Tools，可以在安装时手动添加宏定义跳过错误：

pip install webview --global-option=build_ext --global-option="-DPATH_MAX=260"

方法3：切换到活跃维护的分支库 #

原webview库的0.1.5版本存在Windows兼容性问题，且可能已停止维护，建议安装其活跃分支pywebview：

pip install pywebview

内容的提问来源于stack exchange，提问作者Rounak77382