This application is an user mode sandbox. It uses the ptrace library to 
supervise the execution of an untrustable application. The sandbox rules 
are defined in sandboxRules.c and file access in file_functions.c. 

To build s4g, you need glibc and some kernel include files, one you have 
that, just tape make and it should compile just fine.

To use s4g, add "sandbox" in front of your command and your application 
will be sandboxed. If your application breaks one of the sandbox rules, 
it will be stopped.

For any question, feel free to contact me at tmorlier @ lri.fr