I just want to copy a folder tree to another place like this:
cp -avr /blah/blah/htdocs ./
but I got error:
cp: the -R and -r options may not be specified together.
I followed this tutorial: http://www.cyberciti.biz/faq/copy-folder-linux-command-line/
It's about Linux, while I am using Mac. I found I can work around by using -avR instead.
However, I am wondering why -avr could result in the odd error on Mac.