vim paste in byobu fails if origin file is not closed

Question

I connect my server(centos 7) with putty, and run vim in byobu.
Now I have 2 windows in byobu, and two files, a.py in window-1 and b.py in window-2.
I tried copy some text from a.py to b.py, but ran into some problems.
If I follow steps below, it works fine:

STEP1: In window-1, open a.py, press yy, then quit with :wq
STEP2: In window-2, open b.py, press p.

But if I keep a.py, and b.py open at first , or doest quit a.py after yy, paste fails. It seems quite odd, did missed anything?

I have set clipboard=unnamedplus in .vimrc, and have +clipboard in vim --version, my vim version is 8.2.1438.

Answer 1

You are able to paste across Vim sessions because of the [viminfo] file. By default, Vim stores the contents of non-empty registers (including the default register) into the viminfo file. That's why when you put (with p) right after you start Vim, you get the contents you last yanked (with yy) before you quit Vim last time.

The viminfo file is written right before Vim quits, and it's read during Vim initialization. That's why this won't work automatically if you start the second instance of Vim before you quit the first instance. Then the viminfo file will be read too early by the second instance (or written too late by the first instance) to allow you to put the yanked text across instances.

You can explicitly write the viminfo file with the :wviminfo or wv command. And you can explicitly read it with the :rviminfo or :rv command. So you could use these two commands in the two separate instances to transfer the register information through the viminfo file without having to quit them.

I have set clipboard=unnamedplus in .vimrc, and have +clipboard in vim --version.

If you're using the X11 clipboard integration, you could use that to share copied contents between Vim instances. Note that setting the 'clipboard' option only affects yanks, so to put from the clipboard register you'd have to use "+p.

But this assumes you have a valid X11 server to connect to, which is quite unlikely in your situation. First, since you're connecting through SSH using PuTTY, you would need to use SSH forwarding to export an X11 server from your client. Since you're using PuTTY, I'm assuming you're on a Windows box, which doesn't really run X11 by default, so you'd have to install one and run it (easier said than done.) Also, since you're running Byobu, you will also have trouble reconnecting to an existing Byobu session, which will quite likely be pointing at an invalid X11 server, using the connection information at the time the Byobu session was created, which may no longer match the new X11 forwarding connection information of the new SSH session... It'spossible to make this all work, but if you want my opinion, it's probably too much trouble, especially for this particular use case of two Vim instances in the same remote box.