From: matz@... (Yukihiro Matsumoto)
Date: 2004-07-03T10:57:40+09:00
Subject: Re: ruby-dev summary 23763-23840

Hi,

In message "Re: ruby-dev summary 23763-23840"
    on 04/07/03, Paul Brannan <pbrannan@atdesk.com> writes:

|>   2. set_trace_func should be prohibited in $SAFE>0.
|> 
|>      -> Matz stated that $SAFE>3 check is enough,
|>         because we are trusting $SAFE<=3 codes.
|
|I'm not sure I agree.  I don't think it should ever be possible to
|downgrade your $SAFE level without help from a thread that already has
|its $SAFE level downgraded, but it is:

<snip>

|I'd have to be malicious to write code like this, and potentially
|malicious code shouldn't be executed in $SAFE=1, but if explicitly
|setting $SAFE is disallowed, then so should the above code.

Define "malicious" before saying "shouldn't". ;-)

|Is there a practical use calling set_trace_func when $SAFE=1?

For exmaple, running a debugger on -T1 program.

							matz.