in vim, with
I get the number of all buffers the same with
how I can get the total number of buffers ?
Same idea than Heptite's solution, but as a one liner. Many other things may be done this way: get the name of the buffer (thanks to map), wipeout buffers that match a pattern, https://stackoverflow.com/questions/2974192/how-can-i-pare-down-vims-buffer-list-to-only-include-active-buffers/2974600#2974600n etc.
echo len(filter(range(1, bufnr('$')), 'buflisted(v:val)'))
To my knowledge there is no built-in method in Vim to do this, but you could create a function:
function! NrBufs() let i = bufnr('$') let j = 0 while i >= 1 if buflisted(i) let j+=1 endif let i-=1 endwhile return j endfunction
Put the above in a text file with its name ending in .vim, :source it, then you can do something like:
:let buffer_count = NrBufs() :echo buffer_count
June 21 note: If you have a recent version of Vim as of 2017, Gid's answer below is the optimal solution.