;;; examples/safe/evil.scm -- Evil Scheme file to be run in a safe ;;; environment. ;;; Commentary: ;;; This is an example file to be evaluated by the `safe' program in ;;; this directory. This program, unlike the `untrusted.scm' (which ;;; is untrusted, but a really nice fellow though), tries to do evil ;;; things and will thus break in a safe environment. ;;; ;;; *Note* that the files in this directory are only suitable for ;;; demonstration purposes, if you have to implement safe evaluation ;;; mechanisms in important environments, you will have to do more ;;; than shown here -- for example disabling input/output operations. ;;; Author: Martin Grabmueller ;;; Date: 2001-05-30 ;;; Code: (define passwd (open-input-file "/etc/passwd")) (let lp ((ch (read-char passwd))) (if (not (eof-object? ch)) (lp (read-char passwd)))) ;;; End of file.