title: ./test.ksh[9]: [: argument expected
body: <p>We are running to script to find the zfs file system monitoring and having error as below.
  argument expected</p>
  
  <pre><code>#!/bin/sh
  USED_SPACE_PERCENT_WARN=20
  PATH=/usr/bin:/usr/sbin; export PATH
  # check zfs File system
  if [ `df -F zfs | wc -l` -gt 0 ]; then
    /usr/sbin/zpool list -H | while read line
    do
      USED_SPACE_PERCENT=`echo "$line" | nawk -F'[    % ]+' '{print $5}'`
      if [ $USED_SPACE_PERCENT -gt $USED_SPACE_PERCENT_WARN ]; then
        POOL=`echo "$line" | nawk -F'[      % ]+' '{print $1}'`
        echo "ZFS pool $POOL has used $USED_SPACE_PERCENT% of its space."
      fi
    done
  fi
  </code></pre>