A Chicken Scheme macro for temporarily changing the current working directory

with-current-directory.scm

;;; Preserve the current working directory, then change to a new directory
;;; DIR and evaluate THUNK. Finally, restore the working directory and
;;; return THUNK's value.
;;;
;;; Uses dynamic-wind, so it's signal- and continuation-safe.
;;;
;;; Works with Chicken Scheme.

(use posix)

(define (with-current-directory dirname thunk)
  (let ((cwd (current-directory)))
    (dynamic-wind
      (lambda () (change-directory dirname))
      thunk
      (lambda () (change-directory cwd)))))

;;; Example: should print "/" and return 5.

(with-current-directory "/"
  (lambda ()
    (print (current-directory))
    3
    4
    5))