copy.el

(require 'f)
(defun current-line-number ()
  "Print the current line number (in the buffer) of point."
  (interactive)
  (save-restriction
    (widen)
    (save-excursion
      (beginning-of-line)
      (1+ (count-lines 1 (point))))))

(defun my-copy-current-line-info ()
  (interactive)
  (let ((path (f-this-file)))
    (when (not (null path))
      (kill-new (format "%s L%s"
                        (f-filename (f-this-file))
                        (current-line-number))))))