Add a Drush alias in Emacs

drush-site-alias.el

(defcustom drush-default-alias-file "~/.drush/aliases.drushrc.php"
  "Default drush configuration directory."
  :type 'string
  :group 'drupal)

(defun drupal-drush-alias-add (name uri root) 
  "Add an alias to the drush aliases file in a buffer."
  (interactive "sAlias Name: \nsURI: \nsRoot: ") 
  (drupal-drush-process-alias-file drush-default-alias-file name uri root))

(defun drupal-drush-process-alias-file (file name uri root)
  "Read the contents of a file into a temp buffer and then do
 something there."
  (when (file-readable-p file)
    (let (mybuffer)
      (setq mybuffer (find-file file))
      (goto-char (point-max))
      (insert (format "$aliases['%s'] = array(\n" name))
      (insert (format "  'uri' => '%s',\n" uri))
      (insert (format "  'root' => '%s',\n" root))
      (insert (format ");\n"))
      )))