fix 'btrfs check' running status not detected correctly

plugins/dynamix/scripts/btrfs_check

@@ -1,7 +1,7 @@
 #!/bin/bash
 # btrfs_check start <dev> <id> <options> 
 # btrfs_check status <dev> <id>
-# btrfs_check cancel <dev> 
+# btrfs_check cancel <dev> <id>
 
 case "$1" in
 'start')
@@ -13,9 +13,14 @@ case "$1" in
   else
     echo "Not available"
   fi;
-  pgrep -f "/sbin/btrfs_check.*$2" >/dev/null
+  # establish retval of this script: 0 running, 1 not running
+  pgrep -f "/sbin/btrfs check .*$2" >/dev/null
 ;;
 'cancel')
   pkill -f "/sbin/btrfs_check.*$2"
+  while pgrep -f "/sbin/btrfs check .*$2" >/dev/null ; do
+    sleep 1
+  done
+  echo "Cancelled" >> /var/lib/btrfs/check.status.$3
 ;;
 esac

plugins/dynamix/scripts/btrfs_scrub

@@ -6,9 +6,9 @@
 case "$1" in
 'start')
   # one might wonder: why exec the scrub command, passing -B and put in background, vs just
-  # executing scrub without -B and without explicit background.  It's because it handles case
+  # executing scrub without -B and without explicit background?  It's because it handles case
   # where user adds -B themselves as one of the options, which would hang webGui process until
-  # scrub completes which would not be good.  btrfs balance does not have this btw.
+  # scrub completes, which would not be good.  (btrfs balance does not have -B option btw)
   exec /sbin/btrfs scrub start -B $3 $2 &>/dev/null &
 ;;
 'status')