stack.erp5: Abort also if pidfile cannot be read.

stack/erp5/buildout.hash.cfg

@@ -15,7 +15,7 @@
 # not need these here).
 [mariadb-resiliency-after-import-script]
 filename = instance-mariadb-resiliency-after-import-script.sh.in
-md5sum = 5fc1bb6ade3458e0c2970c31ca7157ea
+md5sum = 1e89de954d816b93f76d9b75820d192c
 
 [template-mariadb]
 filename = instance-mariadb.cfg.in

stack/erp5/instance-mariadb-resiliency-after-import-script.sh.in

@@ -23,7 +23,11 @@ update_executable='${update-mysql:output}'
 
 # Make sure mariadb is not already running
 if [ -e "$pid_file" ]; then
-  pid=$(cat "$pid_file") > /dev/null 2>&1
+  pid=$(cat "$pid_file")
+  if [ $? -ne 0 ]; then
+    echo "Cannot read Mariadb pidfile, assuming running. Aborting."
+    exit 1
+  fi
   if kill -0 "$pid"; then
     echo "Mariadb is already running with pid $pid. Aborting."
     exit 1