exe/sym in sym-3.0.0 vs exe/sym in sym-3.0.1

@@ -1,22 +1,22 @@
 #!/usr/bin/env ruby
 # vim: ft=ruby
 
 require_relative '../lib/ruby_warnings'
 
-lib_path = File.expand_path(File.dirname(__FILE__) + '/../lib')
+lib_path = File.expand_path("#{File.dirname(__FILE__)}/../lib")
 $LOAD_PATH << lib_path if File.exist?(lib_path) && !$LOAD_PATH.include?(lib_path)
 
 require 'sym'
 require 'sym/app'
 
 # ARGV.any?{ |a| a =~ /^-/ } ?
 begin
   exit ::Sym::App::CLI.new(ARGV.dup).execute
 rescue Interrupt => e
-  STDERR.flush
+  $stderr.flush
   warn "Interrupt, #{e.message}, exiting."
-  STDERR.flush
+  $stderr.flush
   exit 1
 end