> touch /tmp/foo/bar

> chmod ugo-x /tmp/foo

> irb

jruby-1.6.2 :001 > dir = "/tmp/foo"
 => "/tmp/foo"

jruby-1.6.2 :002 > File.lstat dir
 => #<File::Stat dev=0x801, ino=278533, mode=040644, nlink=2, uid=4473, gid=1015, rdev=0x0, size=4096, blksize=4096, blocks=8, atime=Thu Jul 14 17:46:23 +1200 2011, mtime=Thu Jul 14 17:42:26 +1200 2011, ctime=Thu Jul 14 17:42:45 +1200 2011>

jruby-1.6.2 :003 > Dir.foreach(dir) {|e| File.lstat File.join(dir, e)}
Errno::ENOENT: No such file or directory - /tmp/foo/.
	from org/jruby/RubyFile.java:1510:in `lstat'
	from (irb):2:in `evaluate'
	from org/jruby/RubyDir.java:389:in `foreach'
	from (irb):2:in `evaluate'
	from org/jruby/RubyKernel.java:1088:in `eval'
	from ~/.rvm/rubies/jruby-1.6.2/lib/ruby/1.8/irb.rb:158:in `eval_input'
	from ~/.rvm/rubies/jruby-1.6.2/lib/ruby/1.8/irb.rb:271:in `signal_status'
	from ~/.rvm/rubies/jruby-1.6.2/lib/ruby/1.8/irb.rb:155:in `eval_input'
	from org/jruby/RubyKernel.java:1419:in `loop'
	from org/jruby/RubyKernel.java:1191:in `catch'
	from ~/.rvm/rubies/jruby-1.6.2/lib/ruby/1.8/irb.rb:154:in `eval_input'
	from ~/.rvm/rubies/jruby-1.6.2/lib/ruby/1.8/irb.rb:71:in `start'
	from org/jruby/RubyKernel.java:1191:in `catch'
	from ~/.rvm/rubies/jruby-1.6.2/lib/ruby/1.8/irb.rb:70:in `start'
	from ~/.rvm/rubies/jruby-1.6.2/bin/irb:17:in `(root)'

> rvm use 1.9.2

> irb

ruby-1.9.2-p0 :001 > dir = "/tmp/foo"
 => "/tmp/foo"

ruby-1.9.2-p0 :002 > File.lstat dir
 => #<File::Stat dev=0x801, ino=278533, mode=040644, nlink=2, uid=4473, gid=1015, rdev=0x0, size=4096, blksize=4096, blocks=8, atime=2011-07-14 17:46:23 +1200, mtime=2011-07-14 17:42:26 +1200, ctime=2011-07-14 17:42:45 +1200>

ruby-1.9.2-p0 :003 > Dir.foreach(dir) {|e| File.lstat File.join(dir, e)}
Errno::EACCES: Permission denied - /tmp/foo/.
	from (irb):3:in `lstat'
	from (irb):3:in `block in irb_binding'
	from (irb):3:in `foreach'
	from (irb):3
	from ~/.rvm/rubies/ruby-1.9.2-p0/bin/irb:17:in `<main>'

> rvm use 1.8.7

> irb

ruby-1.8.7-p334 :001 > dir = "/tmp/foo"
 => "/tmp/foo"

ruby-1.8.7-p334 :002 > File.lstat dir
 => #<File::Stat dev=0x801, ino=278533, mode=040644, nlink=2, uid=4473, gid=1015, rdev=0x0, size=4096, blksize=4096, blocks=8, atime=Thu Jul 14 17:46:23 +1200 2011, mtime=Thu Jul 14 17:42:26 +1200 2011, ctime=Thu Jul 14 17:42:45 +1200 2011>

ruby-1.8.7-p334 :003 > Dir.foreach(dir) {|e| File.lstat File.join(dir, e)}
Errno::EACCES: Permission denied - /tmp/foo/.
	from (irb):3:in `lstat'
	from (irb):3
	from (irb):3:in `foreach'
	from (irb):3