On Fri, 22 Sep 2006 09:14:37 +0100, re2823 wrote: > I have a strange problem: I have an iso image file which (according to ls) > is 569M in size: > > ... > > Now for the problem... > The relevant line from "df -h": > poota:~# df -h > Filesystem Size Used Avail Use% Mounted on /root/image.iso > 569M 569M 0 100% /root/temp > > And the result from running "du -sh": poota:~# du -sh temp/ > 1.1G temp/ > > Just to really baffle me, I've burnt this iso image onto a 650MB CD-ROM, > mounted it, and it too has 1.1GB of data on it: > > poota:~# du -sh /media/cdrom0 > 1.1G /media/cdrom0 > > But the "df -h" output seems more reasonable: server:~# df -h > Filesystem Size Used Avail Use% Mounted on /dev/hdd > 569M 569M 0 100% /media/cdrom0 > > Could anyone please tell me how there can be such a huge difference > between the output from df and du?
Are you using some kind Live CD? This is actually quite normal for Live CDs. > My real problem comes when I want to remove one small file from the file > system, and turn it back into an iso - the resulting iso image is 1.1GB > (and I can no longer write it to a CD!) It maybe helpful if you had indicated what CD you are using. They must be using some kind of compression. So, df count on file size reported by OS (HD/CD sectors), while du count on file sizes reported by themselves (byte count), thus, df reports compressed file sizes while du reports uncompressed file sizes. Check out the mkisofs -z option, for example. ,----- | -z Generate special RRIP records for transparently compressed | files. This is only of use and interest for hosts that support | transparent decompression, such as Linux 2.4.14 or later. You | must specify the -R or -r options to enable RockRidge, and gen- | erate compressed files using the mkzftree utility before running | mkisofs. Note that transparent compression is a nonstandard | Rock Ridge extension. The resulting disks are only transpar- | ently readable if used on Linux. On other operating systems you | will need to call mkzftree by hand to decompress the files. `----- Most Live CDs use other kind of compression, eg, squashfs. HTH tong -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
