On MacOS, Oha crashes when "Too many open files"

[hatoo]

[hatoo]

tokio-rs/tokio#2324

[hatoo]

Maybe limiting -c value based on ulimit -n is better.

[hatoo]

PR on rustc to prevent access to /dev/urandom
rust-lang/rust#70207

[hatoo]

rust-lang/rust#70207 has landed on rust 1.44
https://github.com/rust-lang/rust/blob/1.44.0/src/libstd/sys/unix/rand.rs