From: akr@... Date: 2021-06-17T06:53:09+00:00 Subject: [ruby-core:104334] [Ruby master Feature#16962] Make IO.for_fd autoclose option default to false Issue #16962 has been updated by akr (Akira Tanaka). We don't close 0 (stdin), 1 (stdout), 2 (stderr) because they can be used from various library. If we close 2, next open() return 2. Assume that we open a database file. If open() returns 2 for the database, the database would be corrupted when ruby raises an error that error messages are printed to stderr. I feel that IO.for_fd with autoclose=true is appropriate for applications which takes a file descriptor as a command line option. (valgrind --log-fd=FD, etc.) In that case, IO object created by IO.for_fd should closed when the IO object is garbage collected. I agree that autoclose=false is appropriate for testing but I guess real applications need autoclose=true more. ---------------------------------------- Feature #16962: Make IO.for_fd autoclose option default to false https://bugs.ruby-lang.org/issues/16962#change-92554 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal ---------------------------------------- I discussed this with @eregon and I think the goal here is to try and figure out a way these interfaces can be a bit less confusing. ## 1. I don't understand this behaviour: ```ruby STDOUT.close STDOUT.puts "Hello World" # => closed stream ``` vs ```ruby IO.for_fd(STDOUT.fileno, autoclose: true).close STDOUT.puts "Hello World" # => Hello World ``` ## 2. `IO.for_fd(..., autoclose: true/false)` The documentation for `autoclose` is: > If the value is false, the fd will be kept open after this IO instance gets finalized. But it also seems to affect `#close` - i.e. calling close does not close underlying file descriptor. Should we fix the documentation or is the implementation wrong? Maybe the name `autoclose:` is very confusing. My initial interpretation was it was just 'automatically close this I/O when it is garbage collected'. ## 3. `IO.for_fd(..., autoclose: false)` default In most cases, it seems like `autoclose: false` would make more sense as the default, since the file descriptor must come from some other place. -- https://bugs.ruby-lang.org/ Unsubscribe: