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+# To the extent possible under law, Eric Wong has waived all copyright and
+# related or neighboring rights to this examples
+#
+# Multi-Processing-safe monkey patch for Logger
+#
+# This monkey patch fixes the case where "preload: true" is used and
+# the application spawns a background thread upon being loaded.
+#
+# This removes all lock from the Logger code and solely relies on the
+# underlying filesystem to handle write(2) system calls atomically when
+# O_APPEND is used.  This is safe in the presence of both multiple
+# threads (native or green) and multiple processes when writing to
+# a filesystem with POSIX O_APPEND semantics.
+#
+# It should be noted that the original locking on Logger could _never_ be
+# considered reliable on non-POSIX filesystems with multiple processes,
+# either, so nothing is lost in that case.
+
+require 'logger'
+class Logger::LogDevice
+  def write(message)
+    @dev.syswrite(message)
+  end
+
+  def close
+    @dev.close
+  end
+end