rapid7/metasploit-framework — pull request #1974 by wchen-r7 (2013-06-17 21:09:08+00:00)
Title: Update on the usage of sleep()

sleep() used to cause issues on an older version of Ruby. This is no longer the case since 1.9, and we also actually have Rex::sleep() that's just a wrapper for select(). We should mention all this in HACKING.