Unfortunately at the moment, it's not a safe call that any particular system is actually running a modern enough kernel imo. getrandom() showed up in 3.17, and

Unfortunately at the moment, it's not a safe call that any particular system is actually running a modern enough kernel imo. getrandom() showed up in 3.17, and the latest CentOS distribution ships with 3.10. And then you've got older deployments. You could play with autoconf hell of detecting getrandom() and compiling for it if needed, but I couldn't imagine it to be worth the effort at the moment if you're going to be maintaining a branch of fallback code anyway.