update

1 files changed, 7 insertions, 11 deletions

diff --git a/bin/isdarktty b/bin/isdarktty
index 8d01b89..334d8a0 100755
--- a/bin/isdarktty
+++ b/bin/isdarktty
@@ -1,20 +1,16 @@
 #!/bin/sh
 
-# compute luminance of the current terminal
+# Check darkness by computing luminance of the current terminal.
 
-oldstty=$(stty -g)
+trap "stty $(stty -g)" EXIT
 stty raw -echo min 0 time 0
-printf "\e]11;?\e\\"
+printf '\e]11;?\e\\'
 sleep 0.01
-read -r answer
-stty "$oldstty"
 
-awk -v s="$answer" 'BEGIN {
-	hex="123456789abcdef"
-	split(s, a, "")
-	r = (16 * index(hex, a[10]) + index(hex, a[11])) / 255
-	g = (16 * index(hex, a[15]) + index(hex, a[16])) / 255
-	b = (16 * index(hex, a[20]) + index(hex, a[21])) / 255
+awk -v FS='' -v hex=123456789abcdef '{
+	r = (16 * index(hex, $10) + index(hex, $11)) / 255
+	g = (16 * index(hex, $15) + index(hex, $16)) / 255
+	b = (16 * index(hex, $20) + index(hex, $21)) / 255
 	# print 0.33 * r + 0.5 * g + 0.16 * b
 	exit (0.33 * r + 0.5 * g + 0.16 * b > 0.5)
 }'