lisp/env.el

   1 ;;; setenv.el --- functions to manipulate environment variables.
   2
   3 ;; Maintainer: FSF
   4 ;; Last-Modified: 16 Mar 1992
   5 ;; Keywords: extensions
   6
   7 ;;; Copyright Free Software Foundation 1991
   8
   9 ;;; This file is part of GNU Emacs.
  10
  11 ;;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;;; it under the terms of the GNU General Public License as published by
  13 ;;; the Free Software Foundation; either version 2, or (at your option)
  14 ;;; any later version.
  15
  16 ;;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;;; GNU General Public License for more details.
  20
  21 ;;; You should have received a copy of the GNU General Public License
  22 ;;; along with GNU Emacs; see the file COPYING.  If not, write to
  23 ;;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  24
  25 ;;; Code:
  26
  27 (defun setenv (variable value)
  28   "Set the value of the environment variable named VARIABLE to VALUE.
  29 VARIABLE and VALUE should both be strings.
  30 This function works by modifying process-environment."
  31   (if (string-match "=" variable)
  32       (error "name of environment variable contains an '=' character")
  33     (let ((pattern (concat "^" (regexp-quote (concat variable "="))))
  34           (scan process-environment))
  35       (while scan
  36         (cond
  37          ((string-match pattern (car scan))
  38           (setcar scan (concat variable "=" value))
  39           (setq scan nil))
  40          ((null (setq scan (cdr scan)))
  41           (setq process-environment
  42                 (cons (concat variable "=" value) process-environment))))))))
  43
  44 (provide 'setenv)
  45
  46 ;;; setenv.el ends here