How to copy a file and replace (if necessary) in the target directory from terminal If I'm on my Desktop and I have a file called 'test.txt' on there, and I want to copy that file to say '~/Library/Folder 1/Folder 2/' how do I do that? Also, if there's already a file there called 'test.txt' I'd like to replace that file.

I've tried running 

cp -R ./test.txt ~/Library/Folder 1/Folder 2/ 


but that didn't do the trick.
First things first, -R is used for recursive copying, which won't do anything for a single file. 

cp default behavior is to overwrite the existing file. 

cp test.txt ~/Library/Folder\ 1/Folder\ 2/


The backslash is used to stop the string being split on the spaces.