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[LI] file size ambiguity- report



hello everyone,
    here is the report i promised regarding the file size discrepency in
diff file systems..

how i tested :
    took a huge tar file ( 7 odd mb ) and split it into 6 parts. copied
the original and the split files and the original into a fat32 partition
using the -t msdos option of mount. played around with the files to get
this result and i have my final report in the end which is mostly wrong
;-) someone plz correct me.

what i did :
    when i checked the file sizes in both partitions using du -a -b -c
-k options the problem cropped up. split files of 1211kb ( in ext2fs)
were shown as 1208kb ( reduced in size ) and the original file which was
7248kb was showed as 7220kb. i then concatenated the split files and
found this new file to be 7220kb itself! i then untared the file and the
operation caused no problems at all the original data was obtained. ( no
data loss inspite of size reduction ) i now was surprised and shifted
this new concatenated file to a different directory in ext2fs and the
size was shown as 7248kb by du.( got back its original size ) untarring
the file was no problem and i was amazed by this. so i checked the file
sizes of individual files by ls -l option and guess what the files
occupied the same amount of bytes in both the file systems... no data
loss but only difference in the report from du on fat32 partition.

result:
    du has a bug when working on fat32 file systems. ( am i right here
?? ) shall i report it to the email id given in the man pages ??

interesting facts :
    files of size 1kb were shown as 4kb in du ( logical as each sector
in ext2fs and fat32 is 1kb and 4kb respectively )
    files of size 40kb were shown as 40kb by du ( logical again to the
above reason )
    tar files of size 40kb showed as 40kb ( the earlier was a text file
)
    tar file of size 701kb was showed as 700kb???? ( reasons for my
testing ) why the reduction ???
    directory of 5 kb ( 3kb file + 1kb file + 1kb directory info ) was
showed as 12 kb ( logical again---- 4kb each for the files and the
directory info )
    tar file of 308kb was retained as 308kb ( logical again )

any comments anybody ??? i seriously want to know what all of u have to
say abt this.... if u feel this is a wastage of bandwidth .... please
mail me personally and i will later on post a detailed report after
going through all ur comments and thoughts.... as gandalf once said on
the list ;-)

ps : will anyone perform such a test on fat16 partition and come out
with the results ??? i dont have one and hence cant do it ..... i am
really interested to konow more abt this and will look forward to all ur
replies.

now a dumbfounded chetu
signing off
--
Windows 95 is a 32 bit extension
for a 16 bit OS
originally coded for a 4 bit microprocessor
by a 2 bit company
that cant stand 1 bit of competition.


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