How can I save any file with a space within its filename with vi?

Question

I mostly use vim from the terminal by vi command.

I want to create and save a file named something like getting started.txt (there is space between two words). I tried two methods:

Method #1

:sav getting started.txt

but I got an error : E172: Only one file name allowed

Method #2

:sav "getting started.txt"

This time I got : E471: Argument required

How can I achieve what I want?

Answer 1

Escape the space character:

:sav getting\ started.txt

Answer 2

Commenter @ib mentions fnameescape, here's how you can use it:

1. Enter :save and a space.
2. Press Ctrl-R then = to enter expression mode.
3. Enter fnameescape("Your spacey, special character'y file name"). Tab expansion works, so you can probably do fnTabeTab.
4. Press Enter to insert the escaped file name into your command line.

Poster iler.ml suggests a function to do this easily (I've modified his code slightly). Put this in your .vimrc:

" :W and :Save will escape a file name and write it
command! -bang -nargs=* W :call W(<q-bang>, <q-args>) 
command! -bang -nargs=* Save :call Save(<q-bang>, <q-args>) 

function! W(bang, filename) 
    :exe "w".a:bang." ". fnameescape(a:filename) 
endfu 

function! Save(bang, filename) 
    :exe "save".a:bang." ". fnameescape(a:filename) 
endfu