gcl-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Gcl-devel] Re: danger of open


From: Camm Maguire
Subject: [Gcl-devel] Re: danger of open
Date: 30 Oct 2006 14:54:44 -0500
User-agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.2

Greetings!

IMHO, this is a pretty useful feature of GCL, which helps in
auto-decompressing compressed files, outputting straight to a printer,
etc.  It also matches the unix convention of "pipes as file objects"
-- e.g. gnuplot and many other programs work this way.  

Perhaps some predicate on the stream would help?  If memory serves,
the ansi standard has such notions, e.g. 'file-streams'.

Take care,

Matt Kaufmann <address@hidden> writes:

> Hi, Camm --
> 
> Bob Boyer pointed out something scary to me back in May, and I'm
> finally getting around to asking you about it.  He noticed that by
> executing (open "|kill -9 -1") in GCL, you can logout and kill all
> your processes!  Or just start up GCL in Linux, suspend and use ps to
> get the process id -- say it's 23327 -- and then do this to kill your
> GCL:
> 
> (open "|kill -9 23327")
> 
> This is scary from an ACL2 perspective, when I'd expected that open
> just does an open.  I suppose we could look for a first character of
> #\| and cause an error in that case.  But maybe you want to consider
> eliminating this GCL feature?
> 
> Thanks --
> -- Matt
> 
> 
> 

-- 
Camm Maguire                                            address@hidden
==========================================================================
"The earth is but one country, and mankind its citizens."  --  Baha'u'llah




reply via email to

[Prev in Thread] Current Thread [Next in Thread]