From: "jmthomas (Jason Thomas)" Date: 2012-05-04T23:57:00+09:00 Subject: [ruby-core:44872] [Backport93 - Backport #6179] File::pos broken in Windows 1.9.3p125 Issue #6179 has been updated by jmthomas (Jason Thomas). This does not appear to fixed in Ruby 1.9.3p194, however your test case passes. I have created the following failing test case: def test_pos_with_readline t = make_tempfile random = Random.new(1234) open(t.path, "w") do |f| 1000.times do f.puts "X"*random.rand(80) end end i = 0 lines = open(t.path,'r').read.split("\n") open(t.path, "r") do |f| lines.length.times do puts f.pos assert_equal lines[i], f.readline.chomp i += 1 end end end ---------------------------------------- Backport #6179: File::pos broken in Windows 1.9.3p125 https://bugs.ruby-lang.org/issues/6179#change-26454 Author: jmthomas (Jason Thomas) Status: Closed Priority: Normal Assignee: h.shirosaki (Hiroshi Shirosaki) Category: Target version: Calling the pos method on a File in the Windows version of Ruby on 1.9.3p125 moves the file pointer. Thus it can not be called without side effect. -- http://bugs.ruby-lang.org/