That's mainly for historical reasons (select syscall can only handle fds<1024), modern programs can just set their soft limit to their hard limit and not worry

That's mainly for historical reasons (select syscall can only handle fds<1024), modern programs can just set their soft limit to their hard limit and not worry about it anymore: https://0pointer.net/blog/file-descriptor-limits.html https://0pointer.net/blog/file-descriptor-limits.html