On my machine I can put this in my .irbrc
file (located in your home directory):
Kernel.at_exit {
File.open("irb.log", "w") do |f|
f << Readline::HISTORY.to_a.join("\n")
end
}
It creates a file irb.log
that contains your readline history. Irb uses readline for command input. It might be configured not to use readline for some people, I don't know. And maybe the history will be truncated at some point, or maybe it'll be modified by certain commands you do in your irb session... but try it out and see if it works.
If you want the irb prompt and the result of each command to be included in the log, then just use tee to record the output of irb:
$ irb | tee irb.log