libcurl已安装，但是搜索不到

If libcurl is already installed, check that 'pkg-config' is in your
PATH and PKG_CONFIG_PATH contains a libcurl.pc file. If pkg-config
is unavailable you can set INCLUDE_DIR and LIB_DIR manually via:
R CMD INSTALL --configure-vars='INCLUDE_DIR=... LIB_DIR=...'
解决办法
wget https://github.com/curl/curl/releases/download/curl-7_55_0/curl-7.55.0.tar.gz
cd curl-7.55.0
./configure
make
make install