export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/path/to/user2/R/lib
方法一：
cp /path/to/R/etc/Renviron ~/.Renviron
编辑 ~/.Renviron 文件中的 R_LIBS_SITE
R_LIBS_SITE=${R_LIBS_SITE-'/path/to/user1/R/library:/path/to/user2/R/library'}
---
方法二：
export R_LIBS=$R_LIBS:/path/to/user1/R/library:/path/to/user2/R/library
