我正在尝试在 R 中安装 openssl，使用install.packages('openssl')，但我收到一条错误消息：
* installing *source* package ‘openssl’ ...
** package ‘openssl’ successfully unpacked and MD5 sums checked
Found pkg-config cflags and libs!
Using PKG_CFLAGS=
Using PKG_LIBS=-lssl -lcrypto -ldl -lz
------------------------- ANTICONF ERROR ---------------------------
Configuration failed because openssl was not found. Try installing:
* deb: libssl-dev (Debian, Ubuntu, etc)
* rpm: openssl-devel (Fedora, CentOS, RHEL)
* csw: libssl_dev (Solaris)
* brew: openssl (Mac OSX)
If openssl is already installed, check that 'pkg-config' is in your
PATH and …