python > sh

facelock.py

 
 locker = subprocess.Popen([ "mlock" ])
 print("locker "+str(locker.pid)+" spawned")
-matcher = subprocess.Popen([ "./facewaiter.sh" ])
+matcher = subprocess.Popen([ "./facewaiter.py" ])
 print("matcher "+str(matcher.pid)+" spawned")
 
 def waitfor(x, others):

facematcher.py

     "-s", "--show", default=False, action="store_true",
     help="show what the camera sees")
 sub_match.add_argument(
-    "-w", "--wait", type=str, default=None,
+    "-w", "--wait", default=False, action="store_true",
     help="wait for newline on stdin")
 sub_match.add_argument(
     "-t", "--delay", type=int, default=0,

facewaiter.py

+#!/usr/bin/env python
+
+import subprocess
+
+keyboard = "AT Translated Set 2 keyboard"
+battery = "/sys/class/power_supply/BAT0"
+device = "2"
+faces = "faces"
+key = "36"
+
+bat = False
+if battery is not None:
+    with open(f"{battery}/status", "r") as f:
+        s = f.read().strip()
+        if s == "Discharging" or s == "Unknown":
+            bat = True
+
+proc = subprocess.Popen(
+    f"./facematcher.py match --wait --delay 500 --device {device} {faces}/$USER/*",
+    stdin=subprocess.PIPE, shell=True)
+
+if bat:
+    print(f"On battery, so waiting for {key}")
+    subprocess.check_output(
+        f"xinput test '{keyboard}' | grep --line-buffered 'key press   {key}' | " +
+        f"while read -r line; do exit; done",
+        shell=True)
+    print(f"Got {key}.")
+
+proc.stdin.write(b"hello\n")
+proc.stdin.flush()
+exit(proc.wait())

facewaiter.sh

-#!/bin/bash
-
-keyboard="AT Translated Set 2 keyboard"
-battery="/sys/class/power_supply/BAT0"
-device=2
-faces="faces"
-
-if [ -n "$battery" ]; then
-	st="$(cat "$battery/status")"
-	if [ "$st" != "Discharging" ] && [ "$st" != "Unknown" ]; then
-		./facematcher.py match --delay 500 --device "$device" $faces/$USER/*
-		exit $?
-	fi
-fi
-
-rm -f .testfifo
-mkfifo .testfifo
-xinput test "AT Translated Set 2 keyboard" \
-	| grep --line-buffered "key press   36" > .testfifo &
-xpid=$!
-
-rm -f .matchfifo
-mkfifo .matchfifo
-
-matcher() {
-	cat .matchfifo | ./facematcher.py match --delay 500 --device 2 --wait $faces/$USER/*
-}
-matcher &
-matchpid=$!
-trap "kill $matchpid" SIGINT SIGTERM
-
-read <.testfifo
-echo > .matchfifo
-
-kill $xpid
-wait
-
-rm -f .testfifo
-rm -f .matchfifo