If you’d like to copy the contents of the current file (buffer) to the Mac system clipboard, there are a couple of ways of doing this:
Option 1:
Use the terminal utilities to output the files and pipe contents to the clipboard.
:!cat % | pbcopy
Option 2:
Set the vim clipboard to be the system clipboard:
:set clipboard=unnamedplus
Then any yanking and deleting operations in vim will use the system clipboard. So, for example:
ggyG
Option 3:
Looking at the last yank command, did you know you can actually specify the target clipboard within the yank?
gg"*yG
In this command "* is the system clipboard. On some systems it might be "+ instead.

