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7. tech

7.1 And one question, what is the deal with that MAN-addon? I think that I would be extra-nice, if not a addon, just a simple tarball withthe man-pages in plain text.

I absolutely do not distribute tarballs. Please, do not ask. I'm not interested in that. You can found manpages in tgz format on To read this format in Linux requires an addition of new commands like: groff, grotty, tbl, gtbl and soon: they are venerable and still present text formatting tools.

7.2 Is boot_free in the first floppy the number of bytes that the user is not let use _although_ they are free?

What kind of freedom should be that?? This is the MS concept of freedom :-)

or is it a number of bytes magically free'd by the "mu"-script? To be more precise: Change the value (default is 35kb) to what? 10kb or 100kb?

Ok, now I will explain how the sizes are computed by the Mu builder script. The Mu-builder first compute the size of the tree/startup directory: it contains important things like the kernel (startup/boot), the profiles (startup/init) and the basic modules (startup/modules). Let me call thet RAW_SIZE. Next, it compute that:

                BOOT_SIZE= RAW_SIZE + BOOT_FREE

The BOOT_SIZE is the size in Kb of the first (bootable, mountable, ext2fs) segment called BOOT, located at the top of the diskette. Other two segment (ROOT and USR) are appended to BOOT, to form the whole floppy-disk:

                floppy= BOOT+ROOT+USR

They are contingous: you can put on the floppy-disk the three segments with a simple command like:

                # cat BOOT ROOT.gz USR.bz2 > /dev/fd0H1722 (linux)
                c:> copy /b BOOT+ROOT.gz+USR.bz2 a:  (dos)

The exact X-coordinate of the ROOT and USR segment gets computed on-the-fly and stored in the BOOT segment, in a file called startup/boot/info.

The ROOT's X-coordinate is passed to LILO as ramdisk_start=. The USR's X-coordinate is used as "off-set" in the addon loader for USR.

It is for this reason the Mu-builder builds the BOOT as "the last" segment: because it requires full knowledge about sizes and locations of ROOT and USR.

Now, about compressors used: BOOT is not compressed. It is not possible to store it in this form, 1) because the LILO requires to know where is the kernel 2) because I store in it the user-profiles. ROOT is compressed with gzip (it is ROOT.gz), because the linux kernel has an own internal routine able to handle gzipped ramdisk. USR is compressed with bzip2 (it is USR.bz2), but is unpacked by muLinux itself at boot.

After that, a final consideration about ROOT and USR: theyr content is very different. ROOT is a "file-system image", i.e. the exact reproduction of a little Linux-Extended-2 filesystem. USR, instead, is a little tarball, ultra bizipped.

This is the ... technological background behind the first (BASE) muLinux floppy. Hope it helps!

7.3 I see on the screen " ./bin/ps: cannot open /proc/18368//stat: no such file " repeated severaltimes. Why?

I solved this problem in the next rustic "ps": the rustic ps try to list all directory in the form /proc/[0-9]*/ but, often, they disappears while "ps" is working!

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Last update: 23 Oct 2002, Today is Sweetmorn, the 4th day of The Aftermath in the YOLD 3168
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