vendor/num_threads/src/linux.rs

   1 use std::fs;
   2 use std::num::NonZeroUsize;
   3
   4 pub(crate) fn num_threads() -> Option<NonZeroUsize> {
   5     fs::read_to_string("/proc/self/stat")
   6         .ok()
   7         .as_ref()
   8         // Skip past the pid and (process name) fields
   9         .and_then(|stat| stat.rsplit(')').next())
  10         // 20th field, less the two we skipped
  11         .and_then(|rstat| rstat.split_whitespace().nth(17))
  12         .and_then(|num_threads| num_threads.parse::<usize>().ok())
  13         .and_then(NonZeroUsize::new)
  14 }