| H. Peter Anvin <hpa@zytor.com> |
| June 13, 2004 |
| |
| |
| User tools for zisofs: |
| |
| The user tools for zisofs come in two parts: a utility "mkzftree" and |
| mkisofs, which is part of the cdrtools package. cdrtools 1.11a20 or |
| later is required. |
| |
| First create a directory tree containing compressed files: |
| |
| mkzftree input_dir compressed_dir |
| |
| mkzftree will not overwrite an existing directory; you may want to "rm |
| -rf" the directory tree if you are doing this from a script: |
| |
| Second, invoke the patched mkisofs with the -z option: |
| |
| mkisofs -z -R [other options] -o compressed.iso compressed_dir |
| |
| IMPORTANT: you *must* enable RockRidge (-R or -r) since this is an |
| extensions to the RockRidge specification. Without RockRidge, -z will |
| have no effect. |
| |
| Note that if there are files you do not want compressed (for example, |
| files involved in booting, or README files you want to be readable |
| under all circumstances) you can simply put them in a separate tree |
| and not run mkzftree on that tree. |
| |
| mkzftree will not compress files that end up larger when compressed; |
| if you want it to compress the files anyway, you can give the -f |
| option to mkzftree. |
| |
| mkzftree also accepts a -u option (uncompress), which can be used to |
| convert a compressed tree back to normal form. This can be used to |
| read a zisofs CD-ROM on a machine without zisofs kernel support. |
| |
| This version of mkzftree supports a -p option (parallelize.) |
| Specifying -p and a parallelism (e.g. -p4) allows files (up to the |
| number specified) to compress in parallel. Depending on your setup |
| and your data set size, this might speed things up if you are not |
| completely I/O bound. Use -p0 to completely disable parallel |
| execution; this is the default. |
