From: "kosaki (Motohiro KOSAKI)" <kosaki.motohiro@...>
Date: 2012-11-06T02:31:18+09:00
Subject: [ruby-core:48947] [ruby-trunk - Bug #7134] Signal handling bug in Mac OS X


Issue #7134 has been updated by kosaki (Motohiro KOSAKI).


Note: current documentation of Process.kill() uses puts() in trap handler. So, I personally don't think
that IO in trap handler is invalid code.


/*
 *  call-seq:
 *     Process.kill(signal, pid, ...)    -> fixnum
 *
 *  Sends the given signal to the specified process id(s) if _pid_ is positive.
 *  If _pid_ is zero _signal_ is sent to all processes whose group ID is equal
 *  to the group ID of the process. _signal_ may be an integer signal number or
 *  a POSIX signal name (either with or without a +SIG+ prefix). If _signal_ is
 *  negative (or starts with a minus sign), kills process groups instead of
 *  processes. Not all signals are available on all platforms.
 *
 *     pid = fork do
 *        Signal.trap("HUP") { puts "Ouch!"; exit }
 *        # ... do some work ...
 *     end
 *     # ...
 *     Process.kill("HUP", pid)
 *     Process.wait
----------------------------------------
Bug #7134: Signal handling bug in Mac OS X
https://bugs.ruby-lang.org/issues/7134#change-32451

Author: auastro (Andy Kitchen)
Status: Assigned
Priority: Normal
Assignee: nobu (Nobuyoshi Nakada)
Category: 
Target version: next minor
ruby -v: ruby 1.9.3p194 (2012-04-20 revision 35410) [x86_64-darwin12]


On Mac OS X, running the attached program causes the exception below about 1/10 times it is run.

$ ruby hup.rb 
hup.rb:2:in `write': deadlock; recursive locking (ThreadError)
	from hup.rb:2:in `puts'
	from hup.rb:2:in `puts'
	from hup.rb:2:in `block in <main>'
	from hup.rb:6:in `call'
	from hup.rb:6:in `write'
	from hup.rb:6:in `puts'
	from hup.rb:6:in `puts'
	from hup.rb:6:in `<main>'

The expected output is:
> In Hup Handler
>Finished...

or

> Finished...
> In Hup Handler

My ruby is compiled with clang:

$ clang --version
Apple clang version 4.1 (tags/Apple/clang-421.11.65) (based on LLVM 3.1svn)
Target: x86_64-apple-darwin12.2.0
Thread model: posix



-- 
http://bugs.ruby-lang.org/