From: "mame (Yusuke Endoh)" <mame@...>
Date: 2013-02-23T15:22:38+09:00
Subject: [ruby-core:52730] [ruby-trunk - Bug #7917][Assigned] Can't write to a Logger in a signal handler


Issue #7917 has been updated by mame (Yusuke Endoh).

Status changed from Open to Assigned
Assignee set to kosaki (Motohiro KOSAKI)
Target version set to 2.1.0

This issue is arguable, but anyway I don't consider it a showstopper.
I postpone it to 2.1.0.

It is very arguable if the fault is in the code, or in the design of Ruby core.

-- 
Yusuke Endoh <mame@tsg.ne.jp>
----------------------------------------
Bug #7917: Can't write to a Logger in a signal handler
https://bugs.ruby-lang.org/issues/7917#change-36824

Author: mperham (Mike Perham)
Status: Assigned
Priority: Normal
Assignee: kosaki (Motohiro KOSAKI)
Category: 
Target version: 2.1.0
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.


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