emacs_Configuration

Add these line to .emacs file under ~/.emcas to set command key as Meta key:
;;; I prefer cmd key for meta
(setq mac-option-key-is-meta nil
      mac-command-key-is-meta t
      mac-command-modifier 'meta
      mac-option-modifier 'none)

Set emacs start in folder when using C-x C-f command:
Right click the emacs short cut, hit properties and change the start in field to the desired directory.
Set Mac default find file folder:
M-x cd:~/ input your desired folder.// This is not permanent solution, here is the one:
(just put them into .emacs file under your root directory)

(global-set-key (kbd "C-x C-f") 'my-find-file)
(defun my-find-file ()
  "force a starting path"
  (interactive)
  (let ((default-directory "~/scratch/"))
    (call-interactively 'find-file)))

 line number mode: M-x linum-mode

Mac OSX linum-mode issue:

1. ;; Linum mode                                                                                                                                                                                                                         
   (global-linum-mode t)                                                                                                                                                                                                                   
   ;; Offset the number by two spaces to work around some weird fringe glitch                                                                                                                                                                     
   (setq linum-format "  %d ")
   

   　　

2. f
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