def probe

ezx@1.11.0.0 · src/share/say.bend:171

import Base

171# the parent's fd, by number. The child cannot look at its own: that one was
172# replaced with a pipe before this ran. `$1` is the number.
173def probe() -> String:
174  "ppid=; while read -r k v; do case $k in PPid:) ppid=$v;; esac; done < /proc/self/status; readlink /proc/$ppid/fd/$1 2>/dev/null"