From: "kosaki (Motohiro KOSAKI)" <kosaki.motohiro@...>
Date: 2013-02-23T10:40:57+09:00
Subject: [ruby-core:52725] [ruby-trunk - Bug #7917] Can't write to a Logger in a signal handler


Issue #7917 has been updated by kosaki (Motohiro KOSAKI).


Because your example is deadlockable when using 1.9.3 or earlier. 2.0 detect your mistake and tell you.


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Bug #7917: Can't write to a Logger in a signal handler
https://bugs.ruby-lang.org/issues/7917#change-36813

Author: mperham (Mike Perham)
Status: Open
Priority: Normal
Assignee: 
Category: 
Target version: 
ruby -v: 2.0.0-rc2


Looks like Ruby 2.0 does not allow Mutex#lock within a signal handler.  This prevents Logger from working since it uses an underlying mutex.

log writing failed. can't be called from trap context
log writing failed. can't be called from trap context
log writing failed. can't be called from trap context
log writing failed. can't be called from trap context

Here's Ruby code which reproduces the problem:

require 'logger'

LOG = Logger.new(STDOUT)
LOG.info "Now logging!"

trap 'INT' do
  LOG.info "Hello"
end

sleep
LOG.info "Done"

Run it and hit Ctrl-C.


-- 
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