我试图让R(在Windows上运行)从Internet下载一些软件包,但下载失败,因为我无法正确使用必要的代理服务器.当我尝试Windows菜单选项Packages > Install package(s)...并选择一个CRAN镜像时的输出文本是:
> utils:::menuInstallPkgs()
--- Please select a CRAN mirror for use in this session ---
Warning: unable to access index for repository http://cran.opensourceresources.org/bin/windows/contrib/2.12
Warning: unable to access index for repository http://www.stats.ox.ac.uk/pub/RWin/bin/windows/contrib/2.12
Error in install.packages(NULL, .libPaths()[1L], dependencies = NA, type = type) :
no packages were specified
In addition: Warning message:
In open.connection(con, "r") :
cannot open: HTTP status was '407 Proxy Authentication Required'
我知道代理的地址和端口,我也知道自动配置脚本的地址.我不知道调用了什么身份验证,但是当使用代理时(在浏览器和其他一些应用程序中),我会在弹出的对话框窗口中输入用户名和密码.
要设置代理,我尝试了以下各项:
Sys.setenv(http_proxy="http://proxy.example.com:8080")Sys.setenv("http_proxy"="http://proxy.example.com:8080")Sys.setenv(HTTP_PROXY="http://proxy.example.com:8080")Sys.setenv("HTTP_PROXY"="http://proxy.example.com:8080")对于身份验证,我同样尝试将http_proxy_user环境变量设置为:
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