MacVim open vertical split upon launch

How do I make mvim automatically sp开发者_如何学编程lit the window vertically upon launch?

I don't have mvim, but it probably reads ~/.vimrc, so, try adding this line to your ~/.vimrc file:

vsplit

You can use vim +vsplit to make vim run :vsplit after opening.

If anyone is getting here trying to find out about how to get external files to open in vertical splits, use this Terminal command:

defaults write org.vim.MacVim MMVerticalSplit YES 

Source.