The cargo run -q ps -A -e command does report errors.
$ ps -A -e |head -n5
PID TTY TIME CMD
1 ? 00:00:16 systemd
2 ? 00:00:00 kthreadd
3 ? 00:00:00 pool_workqueue_release
4 ? 00:00:00 kworker/R-rcu_gp
$ cargo run -q ps -A -e |head -n5
error: the argument '-A' cannot be used multiple times
Usage: ps [options]
For more information, try '--help'.
The
cargo run -q ps -A -ecommand does report errors.