To get the equivalent of kill line command in emacs for copying purposes, I use the following code snippet.
Just copy paste it in your .emacs file.
(defun copy-line (arg)
"Copy lines (as many as prefix argument) in the kill ring"
(interactive "p")
(kill-ring-save (line-beginning-position)
(line-beginning-position (+ 1 arg)))
(message "%d line%s copied" arg (if (= 1 arg) "" "s")))
(global-set-key "\\M-k" 'copy-line)
If \C is your control key then \M is your alt key.
So generally by default your kill line can be done by \C-k
Now you can also copy a line by doing: \M-k
I don’t remember where I got this bit of code from, I lost those tabs when Firefox crashed.
So I thought I’d just add it in here for later reference.
Hope it helps