From 5de445c9377905bc637e05bbb85aebc87ee24bd1 Mon Sep 17 00:00:00 2001
From: Jocelyn Le Sage <jocelyn@le-sage.com>
Date: Mon, 15 May 2017 11:13:51 -0400
Subject: [PATCH] Adjusted nice permission check to be compatible with debian.

---
 rootfs/etc/cont-init.d/00-app-niceness.sh | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/rootfs/etc/cont-init.d/00-app-niceness.sh b/rootfs/etc/cont-init.d/00-app-niceness.sh
index ded62b0..0c70631 100755
--- a/rootfs/etc/cont-init.d/00-app-niceness.sh
+++ b/rootfs/etc/cont-init.d/00-app-niceness.sh
@@ -10,9 +10,11 @@ set -u # Treat unset variables as an error.
 APP_NICE_CMD=' '
 
 if [ "${APP_NICENESS:-UNSET}" != "UNSET" ]; then
-    APP_NICE_CMD="nice -n $APP_NICENESS"
+    APP_NICE_CMD="$(which nice) -n $APP_NICENESS"
 
-    if ! $APP_NICE_CMD echo &> /dev/null; then
+    # NOTE: On debian systems, nice always has an exit code of `0`, even when
+    # permission is denied.  Look for the error message instead.
+    if [ "$($APP_NICE_CMD true 2>&1)" != "" ]; then
         echo "ERROR: Permission denied to set application's niceness to" \
              "$APP_NICENESS.  Make sure the container is started with the" \
              "--cap-add=SYS_NICE option."