From: pachl <clintpachl@...>
Date: 2008-05-22T08:25:03+09:00
Subject: Multiple processes logging to single file

When using the native ruby logger, is it save to have multiple
processes writing to the same log file?

For instance, I have the following ruby source example:

# test.rb
require 'logger'

log = Logger.new('/tmp/RLOG')

20.times do
  log.error "PID: #{$$}"
  sleep 1
end

log.close
# end test.rb

Then I execute like so:

$ ruby test.rb & ruby test.rb & ruby test.rb

After inspection of the log file, each process logged 20 times, all
messages interleaved of course. It looks like it works, but am I
delusional? I'm on an OpenBSD box. Does the OS handle caching/writing
from multiple sources?

-pachl