Fzf does something like this:
" CTRL-A CTRL-Q to select all and build quickfix list
function! s:build_quickfix_list(lines)
call setqflist(map(copy(a:lines), '{ "filename": v:val }'))
copen
cc
endfunction
let g:fzf_action = {
\ 'ctrl-q': function('s:build_quickfix_list'),
\ 'ctrl-t': 'tab split',
\ 'ctrl-x': 'split',
\ 'ctrl-v': 'vsplit' }
let $FZF_DEFAULT_OPTS = '--bind ctrl-a:select-all'