char path[100];
  snprintf(path, sizeof(path), "/proc/%d", pid);

You're assuming the pid will fit in 93 bytes! The exact same mistake as `char pid[5];`

Jokes aside, sometimes userspace deserves to be broken, and `char pid[5]` is IMO one of those cases. The fact that we treat integers as a scarce reusable resource is bad, and the fact that we now have a second-order process identifier to cover that up is worse.