Why Ruby app servers break on macOS High Sierra and what can be done about it
https://blog.phusion.nl/2017/10/13/why-ruby-app-servers-break-on-macos-high-sierra-and-what-can-be-done-about-it/ [blog.phusion.nl]
2017-10-19 13:55
This error is caused by changes in how fork() behaves in High Sierra.
Another problem that could have been avoided if people read the manual.
Some more info: http://www.sealiesoftware.com/blog/archive/2017/6/5/Objective-C_and_fork_in_macOS_1013.html
source: HN