On Wed, Feb 28, 2024 at 7:45 AM Information via ruby-talk < ruby-talk(a)ml.ruby-lang.org&gt; wrote: There is not a non-blocking version of IO#eof?. That method works by attempting to read a byte and putting it back if successful, and it was coded to always block, much like IO#read. If you want to perform non-blocking reads until the end of the file is reached, require in the io/nonblock extension and use IO#read_nonblock. It's a bit more limited than IO#read, but it will return bytes if they're available, raise an exception (EOFError) if the end of file was reached, or raise an exception (IO::EAGAINWaitReadable) if the read would block because there is currently no data available. See more details here: https://apidock.com/ruby/IO/read_nonblock. -Jeremy