-*- outline -*-

* Overview

This directory includes examples which show how to create and use safe

environments for safe (sand-boxed) execution of Scheme programs.

*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.

The descriptions below assume that you have a working copy of Guile

installed and available with the standard installation prefix

`/usr/local'.

* Included Examples

** safe

The main program, which executes the Scheme code in a file given on

the command line in a safe environment. The following command will

do that with the file `untrusted.scm' (see below.)

$ ./safe untrusted.scm

or

guile -s safe untrusted.scm

** untrusted.scm

This file contains some Scheme code, which will be executed in a

safe environment by the `safe' script.

** evil.scm

This file also contains Scheme code, but it tries to do evil things.

Evaluating this with the `safe' script will abort on those evil

actions.