Re: Language

[Marcus Brinkmann <Marcus.Brinkmann@ruhr-uni-bochum.de>]

On Sat, Jan 16, 1999 at 04:35:12PM -0800, Sam Franc wrote:
> I have been lurking on this group.
> What text do I need to get to interpret what all this language means,
> such as:
> " /dev/hda1   /dos   vfat   defaults,umask=002,uid=0,gid=35   0   0"
> I am a complete novice and want to install Linux, but I see I need to
> learn a new language before I start.

Hi Sam,

now you got two excellent responses, but no answer what the line really
means :) I will try to give that, but bear with me if I assume to much
techno-knowledge. Ask questions!

I realize that this information will be probably too much for you if you
have not installed Linux yet. You probably want to safe this mail somewhere
and return later, when you have more experience. You do *not* need to know
this to install and explore Linux!

The line is, as somebody else said, a line of a table. This table contains
one line for each filesystem which can be mounted. A filesystem is something
like a disk partition, a floppy, or a cdrom. It can even be a remote file
system (Windows user would call it a file share), or a pseudo filesystem for
communication with the operating system kernel (the "proc" file system,
forget about it if you don't understand a word).

The line comes from /etc/fstab  (short for File System TABle).

The first column contains the device file, which tells the system which
device to use, especially which partition on the device. "hd" mean Hard
Disk, "a" means the master on primary IDE controller ("b" is slave, "c" and
"d" secondary IDE controller). The "1" means first primary partition.

So, "/dev/hda1" is the first primary partition on the master disk on primary
IDE controller.

The second column contains the location to mount the file system by default.
In DOS, you use "A:", "B:", "C:" etc to "mount" your partitions. In Windows,
you have "Desktop\C", "Desktop\D", or, in a network,
"network environment\workgroup\fileshare". In Linux, you can choose an
*arbitrary* location, whereever you like. "/dos" means, the user has created
a directory called "dos" in the top level directory ("root" directory), and
he wants to mount the /dev/hda1 partition there. So, if /dev/hda1 has a file
called "foobar" in the top level directory ("C:\foobar" in DOS), you could
access it as "/dos/foobar" under Linux.

The third is some special information about the TYPE of the filesystem. In
Windows, you know that there can be fat, vfat, fat32 filesystems. In Linux,
there are many more, ext2fs is the standard file system for Linux, so you
will see this often. Linux supports all Windows file systems, macintosh,
amiga, some Unix, network file systems etc. You can get a list of supported
filesystems in your kernel with the command "cat /proc/filesystems".

I have:
brinkmds@flora:~$ cat /proc/filesystems
        ext2
        minix
        msdos
        vfat
nodev   proc
        iso9660

This means, proc is not a real filesystems ("nodev"), but the others are.
BTW, iso9660 is the standard file systems for CD ROMS.

The fourth columns contains a list of options to pass to the mount command.
There are many options, the options above mean: "defaults": use all defaults
options (which these are you can find in the documentation). "umask", "gid",
"uid" set the owner, group and permissions of the files. I would recommend
not to worry about these at this stage of learning.

The fifth and sixth columns are a bit cryptic. The fifth is related to some
"dump" command, forget about it for now. The sixth means in which order the
filesystems should be checked at boot time. "0" means, do not check this
file system at boot time. "1" is usually rthe root file system, and "2" all
others.

I hope this clarified thiungs a bit. If you are interested, there is more
information. Try "man fstab", "man mount" in your Linux shell.

Marcus

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