ZLIBC
Zlibc is a read-only compressed filesystem emulation. It allows
executables to uncompress their datafiles on the fly. No kernel patch,
no recompilation of the executables and the libraries is needed. Using
gzip -9, a compression ratio of 1:3 can easily be
achieved! (See examples below). This program has (almost) the same
effect as a (read-only) compressed file system.
How to install it:
To install zlibc, unpack it using tar xfzvvp
zlibc-0.9h.src.tar.gz, and then execute the following commands:
$ ./configure
$ make
$ make install
Then point your LD_PRELOAD variable to /lib/uncompress.o
(on Linux) or to /usr/local/lib/uncompress.o on SunOs or
Solaris.
$ echo 'This is a test' >testfile
$ gzip testfile
$ cat testfile
cat: testfile: No such file or directory
$ LD_PRELOAD=/lib/uncompress.o
$ export LD_PRELOAD
$ cat testfile
This is a test
See the included documentation for further instructions. This
documentation is supplied as a texinfo file. To print it out, do
$ make dvi
$ dvips zlibc.dvi
To generate an info documentation, do
$ make info
You can then browse this documentation using Emac's info mode, or
using a standalone info browser.
You can also generate html, and browse it using your favorite Web
browser:
$ make html
New in release 0.9:
- Solaris support
- GNU autoconf
- Revised documentation
- General cleanup of the sourcetree (a.out support has been phased out)
How it works:
This package overrides the "open" function (and other similar system
call functions) of the C library. this package uses the LD_PRELOAD
variable to redirect the dynamic linker to use the relevant functions
of uncompress.o instead of the shared library.
Examples: (compressed with gzip -9)
|
Before |
After |
| /usr/info/ |
1568KB |
512KB |
| /usr/lib/emacs/19.19 |
6750KB |
2550KB |
|
|
| /usr/local/smalltalk |
326KB |
126KB |
| /usr/local/lib/lisp |
2256KB |
779KB |
|
|
| /usr/lib/*.a |
1094KB |
476KB |
| /usr/X386/lib/*.a |
1110KB |
470KB |
| /usr/include |
655KB | 325KB |
|
|
| /usr/lib/X11/fonts/75dpi/ |
3158KB (1531KB compressed) |
1095KB (gzipped) |
| /usr/lib/X11/fonts/Speedo/ |
530KB (479 compressed) |
373 (gzipped) |
| /usr/lib/X11/fonts/misc/ |
892k (323KB compressed) |
254KB (gzipped) |
|
|
| /usr/TeX/macros/ |
1167KB |
223KB (sic!) |
| /usr/TeX/inputs |
242KB |
74KB |
| /usr/TeX/formats |
779KB |
251KB |
Available files:
There is an zlibc mailing list at zlibc @
www.tux.org . Please send all bug reports to this list.
You may subscribe to the list by sending a message with 'subscribe zlibc @ tux.org' in its body to
majordomo @ tux.org. (N.B. Please
remove the spaces around the "@". I left them there in order to fool
spambots.) Announcements of new zlibc versions will also be sent to
the list, in addition to the linux announce newsgroups. There also
exists an archive of
the mailing list.
The manual for zlibc-0.9g is available here
To contact me, mail me at Alain.Knaff at
poboxes.com .
Last modified: Sun Mar 22 17:10:32 MET 1998