posix_spawnattr_setflags(3) on macOS
The text d92ca3990966, as macOS 10.14.6, macOS 10.14.3, macOS 10.14.2, macOS 10.14.1, macOS 10.13.6, macOS 10.13.5, macOS 10.13.4, macOS 10.13.3, macOS 10.13.2, macOS 10.13.1, macOS 10.13, macOS 10.12.6, macOS 10.12.5, macOS 10.12.4, macOS 10.12.3, macOS 10.12.2, macOS 10.12.1, macOS 10.12 shipped it.
get or set flags on a posix_spawnattr_t