bdf question

UNIX for Advanced & Expert Users
1

Hi all

i am working on script which uses "bdf" output to create excel sheet now when i check "Total" "Used" & "Available" i found that except root everywhere
used + available != total

here is example :
part from bdf output :

filesystem-total-used-available-%used-Mounted on

/dev/vgfnsdev1/lvol23
                   71680000 6753417 60868786   10% /oradata1
/dev/vg00/oracle   15728640 12911737 2667593   83% /oracle

some calculations :

used          free        actual total      actual           shown      
6753417  + 6753417 = 67622203       &     67622203 != 71680000

my script is working fine but why there is difference in actual addition and shown ?

2

It should be helpful if you also post your script.

Regards

3

script is just a perl script which reads "bdf" output redirected to file nothing else just performs some calculations like converting kb -> mb as such ..

i got right results from df -k command...

4

Can you provide command and output from df and bdf commands? This might help in determining the discrepancy.

5

From the bdf man page

     The bdf command does not account for any disk space reserved for swap
      space, or used for the HFS boot block (8 KB, 1 per file system), HFS
      superblocks (8 KB each, 1 per disk cylinder), HFS cylinder group
      blocks (1 KB - 8 KB each, 1 per cylinder group), and inodes (currently
      128 bytes reserved for each inode).  Non-HFS file systems may have
      other items not accounted for by this command.