Copy and paste content from one file to another file in vi

Question

I am working with two files, and I need to copy a few lines from one file and paste into another file. I know how to copy (yy) and paste (p) in the same file. But that doesn

Answer 1

1. Make sure you have the Vim version compiled with clipboard support
   • :echo has('clipboard') should return 1
   • if it returns 0 (for example Mac OS X, at least v10.11 (El Capitan), v10.9 (Mavericks) and v10.8 (Mountain Lion) - comes with a Vim version lacking clipboard support), you have to install a Vim version with clipboard support, say via brew install vim (don't forget to relaunch your terminal(s) after the installation)
2. Enter a visual mode (V - multiline, v - plain, or Ctrlv - block-visual)
3. Select line(s) you wish to copy
4. "*y - to copy selected
5. "*p - to paste copied

P.S:

• you can replace steps 2-5 with the instructions from the answer by JayG, if you need to copy and paste a single line
• to ease selecting lines, you can add set mouse+=a to your .vimrc - it will allow you to select lines in Vim using the mouse, while not selecting extraneous elements (like line numbers, etc.) NOTICE: it will block the ability to copy mouse-selected text to the system clipboard from Vim.