Issue #19624 has been updated by byroot (Jean Boussier). Note: hiding the IO created a regression with the fiber scheduler, since this instance can end up being passed to Ruby code, and it's invalid for Ruby code to touch an hidden object: https://github.com/ruby/ruby/pull/8485 ---------------------------------------- Bug #19624: Backticks - IO object leakage https://bugs.ruby-lang.org/issues/19624#change-104672 * Author: pineman (João Pinheiro) * Status: Closed * Priority: Normal * ruby -v: ruby 3.2.2 (2023-03-30 revision e51014f9c0) [arm64-darwin22] * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- Hi, This code works on ruby 3.0.6: ```ruby `echo` ObjectSpace.each_object(IO) do |io| if ![STDIN, STDOUT, STDERR].include?(io) io.close end end ``` but raises `IOError` on 3.2.2: ``` minimal-repro-case.rb:8:in `close': uninitialized stream (IOError) ``` I found it started failing on ruby 3.1.0 and after, on macOS and Linux. This code is useful for closing unneeded IO objects in forked processes. It looks like backticks is 'leaking' IO objects, waiting for GC, and it didn't used to before 3.1.0. In ruby 3.1.0, inside `rb_f_backquote` in `io.c`, `rb_gc_force_recycle` was removed in favor of `RB_GC_GUARD` (commit `aeae6e2842e`). I wonder if this has something to do with the problem. Is this code incorrect since ruby 3.1.0 or is it a bug in ruby? Thanks. ---Files-------------------------------- minimal-repro-case.rb (109 Bytes) -- https://bugs.ruby-lang.org/