mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-30 08:09:04 +00:00
115 lines
4.2 KiB
EmacsLisp
115 lines
4.2 KiB
EmacsLisp
;;; env.el --- functions to manipulate environment variables.
|
|
|
|
;; Copyright (C) 1991, 1994 Free Software Foundation, Inc.
|
|
|
|
;; Maintainer: FSF
|
|
;; Keywords: processes, unix
|
|
|
|
;; This file is part of GNU Emacs.
|
|
|
|
;; GNU Emacs is free software; you can redistribute it and/or modify
|
|
;; it under the terms of the GNU General Public License as published by
|
|
;; the Free Software Foundation; either version 2, or (at your option)
|
|
;; any later version.
|
|
|
|
;; GNU Emacs is distributed in the hope that it will be useful,
|
|
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
;; GNU General Public License for more details.
|
|
|
|
;; You should have received a copy of the GNU General Public License
|
|
;; along with GNU Emacs; see the file COPYING. If not, write to the
|
|
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
;; Boston, MA 02111-1307, USA.
|
|
|
|
;;; Commentary:
|
|
|
|
;; UNIX processes inherit a list of name-to-string associations from their
|
|
;; parents called their `environment'; these are commonly used to control
|
|
;; program options. This package permits you to set environment variables
|
|
;; to be passed to any sub-process run under Emacs.
|
|
|
|
;;; Code:
|
|
|
|
;; History list for environment variable names.
|
|
(defvar read-envvar-name-history nil)
|
|
|
|
(defun read-envvar-name (prompt &optional mustmatch)
|
|
"Read environment variable name, prompting with PROMPT.
|
|
Optional second arg MUSTMATCH, if non-nil, means require existing envvar name.
|
|
If it is also not t, RET does not exit if it does non-null completion."
|
|
(completing-read prompt
|
|
(mapcar (function
|
|
(lambda (enventry)
|
|
(list (substring enventry 0
|
|
(string-match "=" enventry)))))
|
|
process-environment)
|
|
nil mustmatch nil 'read-envvar-name-history))
|
|
|
|
;; History list for VALUE argument to setenv.
|
|
(defvar setenv-history nil)
|
|
|
|
;;;###autoload
|
|
(defun setenv (variable &optional value unset)
|
|
"Set the value of the environment variable named VARIABLE to VALUE.
|
|
VARIABLE should be a string. VALUE is optional; if not provided or is
|
|
`nil', the environment variable VARIABLE will be removed.
|
|
|
|
Interactively, a prefix argument means to unset the variable.
|
|
Interactively, the current value (if any) of the variable
|
|
appears at the front of the history list when you type in the new value.
|
|
|
|
This function works by modifying `process-environment'."
|
|
(interactive
|
|
(if current-prefix-arg
|
|
(list (read-envvar-name "Clear environment variable: " 'exact) nil t)
|
|
(let* ((var (read-envvar-name "Set environment variable: " nil))
|
|
(oldval (getenv var))
|
|
newval
|
|
oldhist)
|
|
;; Don't put the current value on the history
|
|
;; if it is already there.
|
|
(if (equal oldval (car setenv-history))
|
|
(setq oldval nil))
|
|
;; Now if OLDVAL is non-nil, we should add it to the history.
|
|
(if oldval
|
|
(setq setenv-history (cons oldval setenv-history)))
|
|
(setq oldhist setenv-history)
|
|
(setq newval (read-from-minibuffer (format "Set %s to value: " var)
|
|
nil nil nil 'setenv-history))
|
|
;; If we added the current value to the history, remove it.
|
|
;; Note that read-from-minibuffer may have added the new value.
|
|
;; Don't remove that!
|
|
(if oldval
|
|
(if (eq oldhist setenv-history)
|
|
(setq setenv-history (cdr setenv-history))
|
|
(setcdr setenv-history (cdr (cdr setenv-history)))))
|
|
;; Here finally we specify the args to give call setenv with.
|
|
(list var newval))))
|
|
(if unset (setq value nil))
|
|
(if (string-match "=" variable)
|
|
(error "Environment variable name `%s' contains `='" variable)
|
|
(let ((pattern (concat "\\`" (regexp-quote (concat variable "="))))
|
|
(case-fold-search nil)
|
|
(scan process-environment)
|
|
found)
|
|
(if (string-equal "TZ" variable)
|
|
(set-time-zone-rule value))
|
|
(while scan
|
|
(cond ((string-match pattern (car scan))
|
|
(setq found t)
|
|
(if (eq nil value)
|
|
(setq process-environment (delq (car scan) process-environment))
|
|
(setcar scan (concat variable "=" value)))
|
|
(setq scan nil)))
|
|
(setq scan (cdr scan)))
|
|
(or found
|
|
(if value
|
|
(setq process-environment
|
|
(cons (concat variable "=" value)
|
|
process-environment)))))))
|
|
|
|
(provide 'env)
|
|
|
|
;;; env.el ends here
|