README
1/**************************************************************************\
2* HighLnk 0.2 http://www.thpinfo.com/highlnk/ *
3* Copyright (c) 2004 Thomas Perl <perl.thomas@aon.at> *
4\**************************************************************************/
5
6 This is the 0.2 release of my small-but-powerful HighLnk linux tool.
7
8 The idea behind is, that on read-only media (be it a always read-only
9 mounted hard disk partition or better examples like a CD or DVD), it is
10 not possible to change files.
11
12 If you can't change the files, but you can hard-link them (letting two
13 different filenames point to the same data on the media), you would save
14 <filesize> bytes if a file <a> with <filesize> bytes appears two times
15 in the scanned directory tree. If <a> appears three times, my method
16 would save <filesize> * 2 bytes, and so on..
17
18 I've tried this proof-of-concept version of HighLnk on my slackware-
19 current w/ slackware-9.1 tree. By using SOC, I gained 634MB of disk
20 space using this technique, shrinking the whole tree from ~5,8GB to
21 ~5,1GB. Now is that cool or what? :)
22
23 You can then create a ISO image for burning on CD-ROM by using mkisofs'
24 "-cache-inodes" parameter, which does exactly what I want it to do -
25 preserve the hard links also on CD-ROM and save space this way.
26
27 I got inspired by some Windows XP installation CD which contained both
28 Home and Pro Edition, resulting in more content than the CD could
29 possibly hold, but the fact that there were same files in both Editions
30 clued me in.
31
32 Please, please give me feedback on what you think about this idea (also,
33 if you have any improvements): perl.thomas@aon.at
34
35 -- Thomas Perl, August 18th 2004, 02.21am
36
37 MD5 code taken from
38 http://www.cr0.net:8040/code/crypto/md5/
39
40 Finder inspired by
41 http://groups.google.com/groups?selm=slrnao99jn.be2.h.harders%40pc52.ifw.ing.tu-bs.de
42
43