You'll probably get a better result if you try df with the h switch and total like:
df -h --total>testfile
and send the data to a file testfile.
Now just open testfile and paste the contents
df -h --total>testfile
and send the data to a file testfile.
Now just open testfile and paste the contents
Slackware 13/ArchLinux - C/Assem/Python