From: "Ara.T.Howard" <ahoward@...>
Date: 2004-02-10T10:15:02+09:00
Subject: Re: timeout w/o timeout.rb

On Tue, 10 Feb 2004, Jamis Buck wrote:

> Date: Tue, 10 Feb 2004 09:32:11 +0900
> From: Jamis Buck <jgb3@email.byu.edu>
> Newsgroups: comp.lang.ruby
> Subject: Re: timeout w/o timeout.rb
> 
> Ara.T.Howard wrote:
> 
> >i'm writing some unit tests which do alot of io/select/etc - bad things to mix
> >with a thread based 'timeout' method...  i've been using this instead:
> >
> >  # a timeout method which does not fail when io blocks 
> >  trap 'SIGALRM', 'IGNORE'
> >  class TimeoutError < StandardError; end
> >  def timeout n
> >    begin
> >      trap('SIGALRM'){throw :timeout, TimeoutError.new}
> >      cid = nil 
> >      unless((cid = fork))
> >        sleep n
> >        Process.kill 'SIGALRM', Process.ppid 
> >      else
> >        thrown = 
> >          catch(:timeout) do 
> >            ret = yield
> >            Process.kill 'SIGKILL', cid 
> >            ret
> >          end
> >        raise thrown if TimeoutError === thrown
> >      end
> >    ensure
> >      trap 'SIGALRM', 'IGNORE'
> >    end
> >  end
> >
> >any massive problems with this (this impl is a mega hack i realize)?
> >
> >does it seem like some permutation of this might be useful?  something like
> >Process#timeout perhaps??
> >
> >-a
> >  
> >
> 
> Doesn't Ruby use SIGALRM internally?  I could be wrong, but if it does, 
> you may be asking for trouble by using it in your script.
> 
> - Jamis

ah - good point - and SIGUSR1 would work just as well

-a
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