ssh_config(5) on macOS
The text 535cb4d743d8, as Mac OS X 10.5.2, Mac OS X 10.5.1, Mac OS X 10.5, Mac OS X 10.4.11.x86, Mac OS X 10.4.11.ppc, Mac OS X 10.4.10.x86, Mac OS X 10.4.10.ppc, Mac OS X 10.4.9.x86, Mac OS X 10.4.9.ppc shipped it.
OpenSSH SSH client configuration files