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In the setup phase, Linux installs several types of files connected to the system devices. There are 2281 files present in the "/dev" directory, in RedHat Linux.
UNIX, and therefore Linux, manages the hardware installed in the system through these "devices" files that correspond to the installed hardware or to the hardware to be installed.
Unlike operating systems like DOS (Disk Operating System) that assign an alphabetic letter to each disk, using letters "A" or "B" for floppy disks and the letters from "C" to "Z" for fixed disks, including CD-ROMs, removable disks, network disks; Linux makes and assigns files for all the devices installed on the system.
For example, for the Hard Disk, "hd", the following file devices are present:
[root@heaven /dev]# l hd
hda hda13 hda4
hda9 hdb12 hdb3 hdb8 hdc11
hdc2 hdc7 hdd10 hdd15 hdd6
hdf
hda1 hda14 hda5
hdb hdb13 hdb4 hdb9 hdc12
hdc3 hdc8 hdd11 hdd2 hdd7
hdg
hda10 hda15 hda6
hdb1 hdb14 hdb5 hdc hdc13
hdc4 hdc9 hdd12 hdd3 hdd8
hdh
hda11 hda2 hda7
hdb10 hdb15 hdb6 hdc1 hdc14 hdc5
hdd hdd13 hdd4 hdd9
hda12 hda3 hda8
hdb11 hdb2 hdb7 hdc10 hdc15 hdc6
hdd1 hdd14 hdd5 hde
[root@heaven /dev]# l hd
As we explained in the previous chapters, the letters "a", "b", "c", "d" and "e" are assigned in that order on the installed hard disk in the machine, or on the hard disk that will be installed in the future.
So the first hard disk in the system will be "hda". The first partition on the first disk will be "hda1" while the fourth partition on the second disk will be "hdb4".
As you can read, the file for partition number 10, "hdd10", is listed on the fourth disk (d), which is generally not present in the system.
This means that the system includes all the possible devices. If you need to use hardware that doesn't have a device file, you have to create it manually with the "mknod" program.
The installed device file has been made during the installation phase starting from its "major" and "minor" numbers assigned by the hardware.
For example, the major numbers for the file device relative to the serial and parallel ports are respectively 5 and 6, while the minor numbers are the ordered numbers in the second column.
[root@heaven /dev]# ll lp[0-3] cua[0-3]
crw-rw---- 1 root
uucp 5, 64 Aug 19 08:22 cua0
crw-rw---- 1 root
uucp 5, 65 Aug 19 08:22 cua1
crw-rw---- 1 root
uucp 5, 66 Aug 19 08:22 cua2
crw-rw---- 1 root
uucp 5, 67 Aug 19 08:22 cua3
crw-rw---- 1 root
lp 6, 0 Aug
19 08:22 lp0
crw-rw---- 1 root
lp 6, 1 Aug
19 08:22 lp1
crw-rw---- 1 root
lp 6, 2 Aug
19 08:22 lp2
[root@heaven /dev]#
Another way to display the major and minor number is to use the program "file" :
[root@heaven /dev]# file lp0 hda1
lp0: character special (6/0)
hda1: block special (3/1)
[root@heaven /dev]# ^file^ll
ll lp0 hda1
brw-r----- 1 root
operator 3, 1 Aug 19 08:22 hda1
crw-rw---- 1 root
lp 6, 0 Aug
19 08:22 lp0
[root@heaven /dev]#
To create these files you can consult the documentation
"info" about "mknod", inserting the relative "major" and "minor" numbers.
`mknod': Make block or character special
files
==============================================
`mknod' creates a FIFO, character
special file, or block special
file with the specified name. Synopsis:
mknod [OPTION]... NAME TYPE [MAJOR MINOR]
Unlike the phrase "special
file type" above, the term "special file"
has a technical meaning on Unix: something
that can generate or receive
data. Usually this corresponds to
a physical piece of hardware, e.g.,
a printer or a disk. (These files
are typically created at
system-configuration time.) The
`mknod' command is what creates files
of this type. Such devices can be
read either a character at a time or
a "block" (many characters) at a time,
hence we say there are "block
special" files and "character special"
files.
The arguments after NAME specify the type of file to make:
`p'
for a FIFO
`b'
for a block (buffered)
special file
`c'
for a character
(buffered) special file
`u'
for a character
(unbuffered) special file
When making a block or character
special file, the major and minor
device numbers must be given after the
file type.
The program accepts the following
option. Also see *Note Common
options::.
`-m MODE'
`--mode=MODE'
Set the mode
of created files to MODE, which is symbolic as in
`chmod' and uses
0666 minus the bits set in the umask as the point
of departure.
*Note File permissions::.
RedHat includes the program "MAKEDEV" to install new file devices.
We have also included the program "tpqic02-support-1.9b.tar.g", in the dir "ExternalContribs/Sunsite/pub/Linux/kernel/tapes" that includes some programs for setting up tape models like Wangtek, Emerald, Archive and Mountain.
These files are included for the purpose of inserting new file devices not included in the 1036 files after the installation.
In you have trouble creating the necessary device file for setting up new hardware because you don't know the major/minor numbers, you can contact the hardware vendor or RedHat Systems.
In the directory "/dev" we can find files for any kind of interface:
We advise to setup the following symbolic links:
/dev/mouse
mouse port symbolic
Current mouse device
/dev/tape
tape device symbolic
Current tape device
/dev/cdrom
CD-ROM device symbolic
Current CD-ROM device
/dev/cdwriter CD-writer
symbolic Current CD-writer device
/dev/scanner scanner
symbolic Current scanner device
/dev/modem
modem port symbolic
Current dialout device
/dev/root
root device symbolic
Current root file system
/dev/swap
swap device symbolic
Current swap device
Some of these links can be made in the installation phase.
The "char" and "block" devices
Practically all the devices can be classified in two important file device families:
[root@heaven /dev]# ls -al lp0 cua0
hda1 sda | sort -r
crw-rw---- 1 root
uucp 5, 64 Aug 19 08:22 cua0
crw-rw---- 1 root
lp 6, 0 Aug
19 08:22 lp0
brw-r----- 1 root
operator 8, 0 Aug 19 08:22 sda
brw-r----- 1 root
operator 3, 1 Aug 19 08:22 hda1
[root@heaven /dev]#
"hd", "sd" and "fd"
The best representatives of block family devices are "IDE-EIDE hard disks", hd, SCSI disks, sd and floppy disks, fd.
[root@heaven /dev]# ls hd* sd* fd*
fd0
fd0u1760 fd1h410 fd1u820
hdb11 hdc2
hdd7 sda8
sdc11 sdd2
fd0CompaQ fd0u1840 fd1h420
fd1u830 hdb12 hdc3
hdd8 sda9
sdc12 sdd3
fd0H1440 fd0u1920
fd1h720 hda
hdb13 hdc4
hdd9 sdb
sdc13 sdd4
fd0d360 fd0u2880
fd1h880 hda1 hdb14
hdc5 hde
sdb1 sdc14
sdd5
fd0h1200 fd0u3200
fd1u1040 hda10 hdb15
hdc6 hdf
sdb10 sdc15
sdd6
fd0h1440 fd0u3520
fd1u1120 hda11 hdb2
hdc7 hdg
sdb11 sdc2
sdd7
fd0h1476 fd0u360
fd1u1440 hda12 hdb3
hdc8 hdh
sdb12 sdc3
sdd8
fd0h1494 fd0u3840
fd1u1600 hda13 hdb4
hdc9 sda
sdb13 sdc4
sdd9
fd0h1600 fd0u720
fd1u1680 hda14 hdb5
hdd sda1
sdb14 sdc5
sde
fd0h360 fd0u800
fd1u1722 hda15 hdb6
hdd1 sda10
sdb15 sdc6
sdf
fd0h410 fd0u820
fd1u1743 hda2 hdb7
hdd10 sda11
sdb2 sdc7
sdg
fd0h420 fd0u830
fd1u1760 hda3 hdb8
hdd11 sda12
sdb3 sdc8
sdh
fd0h720 fd1
fd1u1840 hda4 hdb9
hdd12 sda13
sdb4 sdc9
sdi
fd0h880 fd1CompaQ
fd1u1920 hda5 hdc
hdd13 sda14
sdb5 sdd
sdj
fd0u1040 fd1d360
fd1u2880 hda6 hdc1
hdd14 sda15
sdb6 sdd1
sdk
fd0u1120 fd1h1200
fd1u3200 hda7 hdc10
hdd15 sda2
sdb7 sdd10
sdl
fd0u1440 fd1h1440
fd1u3520 hda8 hdc11
hdd2 sda3
sdb8 sdd11
sdm
fd0u1600 fd1h1476
fd1u360 hda9 hdc12
hdd3 sda4
sdb9 sdd12
sdn
fd0u1680 fd1h1494
fd1u3840 hdb hdc13
hdd4 sda5
sdc sdd13
sdo
fd0u1722 fd1h1600
fd1u720 hdb1 hdc14
hdd5 sda6
sdc1 sdd14
sdp
fd0u1743 fd1h360
fd1u800 hdb10 hdc15
hdd6 sda7
sdc10 sdd15
For IDE/EIDE or SCSI hard disk operation, this is clear. Unlike these, floppies depend on the format of the floppy.
For example, for the device file "fd0H1440" we have:
A floppy disk under Linux can be formatted with the "fdformat" command:
[root@heaven /dev]# fdformat /dev/fd0
Double-sided, 80 tracks, 18 sec/track.
Total capacity 1440 kB.
Formatting ... done
Verifying ... done
[root@heaven /dev]#
As you can see, we don't use the specific device (fd0H1440) because Linux knows the type in advance.
Under Linux it's also possible to format hard disk.
Linux, like UNIX, manages communication between the user and the system with I/O devices. All these devices under Linux correspond to the "/dev/tty" files, also called "tty".
The word "tty" means "teletype"; these terminals were slow printers, built by the Teletype Corporation.
These files belong to the "char" family as we can see from the "ls" list :
[root@heaven /dev]# ll tty[0-6]
crw-rw---- 1 root
root 4, 0 Nov 22 05:56
tty0
crw--w---- 1 root
tty 4, 1 Nov 22 15:09
tty1
crw------- 1 root
tty 4, 2 Nov 22 05:56
tty2
crw------- 1 root
tty 4, 3 Nov 22 05:56
tty3
crw------- 1 root
tty 4, 4 Nov 22 05:56
tty4
crw------- 1 root
tty 4, 5 Nov 22 05:56
tty5
crw------- 1 root
tty 4, 6 Nov 22 05:56
tty6
[root@heaven /dev]#
When the system boots by "default" under RedHat Linux, level number 3 (Multi-User) enters into the "init" as we can see in the file "/etc/inittab" (See Chapter 22. Boot and shutdown)
[root@heaven /dev]# more /etc/inittab |
grep getty
# Run gettys in standard runlevels
1:12345:respawn:/sbin/getty tty1 VC linux
2:2345:respawn:/sbin/getty tty2 VC linux
3:2345:respawn:/sbin/getty tty3 VC linux
4:2345:respawn:/sbin/getty tty4 VC linux
5:2345:respawn:/sbin/getty tty5 VC linux
6:2345:respawn:/sbin/getty tty6 VC linux
[root@heaven /dev]#
After any terminal console, from "ALT-F1" to "ALT-F6", there's assigned a corresponding "tty". So "tty1" corresponds to "ALT-F1" and "ALT-F6" corresponds to "tty6".
If we run the command "tty" without any other parameter, the program prints the communication port from where it is interacting with the system.
[root@heaven /root]# tty
/dev/tty4
If we run this command from the graphical X-Window environment, the "tty" will be the pseudo-tty, in other words the virtual terminal assigned automatically by the system.
Running the command "ps" without parameters, we see the actual activated "TTY" channels in the second column.
[root@heaven /root]# ps
PID TTY STAT TIME COMMAND
627 1 S
0:00 (login)
628 2 S
0:00 (getty)
629 3 S
0:00 (getty)
630 4 S
0:00 login root
631 5 S
0:00 (getty)
632 6 S
0:00 (getty)
633 1 S
0:00 (bash)
659 1 S
0:00 (xinit)
660 1 S
1:57 X:0
661 1 S
0:00 (startkde)
677 1 S
0:00 kaudioserver
678 1 S
0:00 kwmsound
679 1 S
0:00 kfm
681 1 S
0:00 kbgndwm
682 1 S
0:00 krootwm
683 1 S
0:02 kpanel
684 1 S
0:25 kwm
685 1 S
0:00 maudio -media 1
696 p0 S
0:00 (bash)
720 1 S
0:00 /opt/kde/bin/kforest.kss -delay 10 -install -corners iiii -nice 0
723 1 S
7:06 /opt/netscape/netscape
724 1 S
0:00 (dns helper)
922 1 S
0:06 kvt -T Terminale
923 p1 S 0:00
bash
1769 1 S
0:00 kvt -T Terminale
1770 p2 S
0:00 bash
2012 p2 S
0:00 mc --color
2014 p3 S
0:00 bash -rcfile .bashrc
2229 4 S
0:00 -bash
2261 1 S
0:00 kvt -T Terminale
2262 p4 S
0:00 bash
2274 1 S
0:00 kvt -T Terminale
2275 p5 S
0:00 bash
2287 1 S
0:00 kvt -T Terminale
2288 p6 S
0:00 bash
2300 p6 S
0:00 vi
2301 p4 S
0:00 top
2302 1 S
0:00 kvt -T Terminale
2303 p7 S
0:00 bash
2315 p7 S
0:00 mc --color
2317 p8 S
0:00 bash -rcfile .bashrc
2329 p5 S
0:00 /usr/visix/lg/lg
2330 p5 S
0:00 fss
2331 p1 R
0:00 ps
[root@heaven /root]#
The memory devices
In the "devices.txt" file we find that the memory devices are the following:
1 char
Memory devices
1 = /dev/mem Physical
memory access
2 = /dev/kmem Kernel virtual
memory access
3 = /dev/null Null device
4 = /dev/port I/O port
access
5 = /dev/zero Null byte
source
6 = /dev/core OBSOLETE
- replaced by /proc/kcore
7 = /dev/full Returns ENOSPC
on write
8 = /dev/random Nondeterministic random
number gen.
9 = /dev/urandom Faster, less secure random
number gen.
Each of these files as listed in the previous table has a specific task in the system. The physical memory is present in the "/dev/mem" file. The "/dev/kcore" file represents the memory size.
For further information we can run the command "man mem".
The "/dev/null" file represents infinite trash. This means that any file that you append to this file will disappear.
[root@heaven /root]# cat /etc/passwd >
/dev/null
[root@heaven /root]# more /dev/null
[root@heaven /root]#
In fact this is a special file.
[root@heaven /root]# file /dev/null
/dev/null: character special (1/3)
[root@heaven /root]#
The major and minor numbers
Like we explain before (i.e Chapter 11 or section devices before) , UNIX and now Linux enumerate device by numbers: eth0, eth1, ... or video0, video1, video2, ... or fd0, fd1, etc.
For example for Harddisk, we have:
[root@ftosx1 /dev]# ls -al hda9
brw-rw---- 2 root
disk 3, 9 May 5
1998 hda9
[root@ftosx1 /dev]#
Now, we know that the "b" in front of the filename means "block" (see before), and also that each file was create in May 5 1998, but what means the numbers "3, 9" on the file "hda9"?
These numbers are called "Major and Minor numbers"!
These numbers are also listed in the file "devices.txt" created and maintained by H. Peter Anvin
Numbers for devices are called "major numbers". For example for SCSI disk the major number is "8".
[root@ftosx1 /dev]# ls -al sda
brw-rw---- 2 root
disk 8, 0 May 5
1998 sda
[root@ftosx1 /dev]#
[root@ftosx1 /dev]# ls -al hda*
brw-rw---- 2 root
disk 3, 0 May 5
1998 hda
[root@ftosx1 /dev]#
Once the device is identified, for example "hda", with this major number "8" ... is possible to start to enumarate the device family (that belong to this major). Minor numbers starts from 0, on the device.
[root@ftosx1 /dev]# ls -al hda*
brw-rw---- 2 root
disk 3, 0 May 5
1998 hda
[root@ftosx1 /dev]#
and then are 1, 2, 3, ... until is necessary. For example, for "/dev/hda" we have
[root@ftosx1 /dev]# ls -al /dev/hda* | sort
brw-rw---- 2 root
disk 3, 0 May 5
1998 /dev/hda
brw-rw---- 2 root
disk 3, 1 May 5
1998 /dev/hda1
brw-rw---- 2 root
disk 3, 2 May 5
1998 /dev/hda2
brw-rw---- 2 root
disk 3, 3 May 5
1998 /dev/hda3
brw-rw---- 2 root
disk 3, 4 May 5
1998 /dev/hda4
brw-rw---- 2 root
disk 3, 5 May 5
1998 /dev/hda5
brw-rw---- 2 root
disk 3, 6 May 5
1998 /dev/hda6
brw-rw---- 2 root
disk 3, 7 May 5
1998 /dev/hda7
brw-rw---- 2 root
disk 3, 8 May 5
1998 /dev/hda8
brw-rw---- 2 root
disk 3, 9 May 5
1998 /dev/hda9
brw-rw---- 2 root
disk 3, 10 May 5
1998 /dev/hda10
brw-rw---- 2 root
disk 3, 11 May 5
1998 /dev/hda11
brw-rw---- 2 root
disk 3, 12 May 5
1998 /dev/hda12
brw-rw---- 2 root
disk 3, 13 May 5
1998 /dev/hda13
brw-rw---- 2 root
disk 3, 14 May 5
1998 /dev/hda14
brw-rw---- 2 root
disk 3, 15 May 5
1998 /dev/hda15
brw-rw---- 2 root
disk 3, 16 May 5
1998 /dev/hda16
[root@ftosx1 /dev]#
and we can read that the minor numbers (like "sons") in sequence. This is the simple and clear rule!.
This is valid for any device, for example for the video the number is "81"!
[root@ftosx1 /root]# cd /dev
[root@ftosx1 /dev]# ls -al video
lrwxrwxrwx 1 root
root
6 Sep 23 14:59 video -> video0
[root@ftosx1 /dev]# ls -al video0
crw------- 1 gorlando root
81, 0 Jan 28 2000 video0
[root@ftosx1 /dev]# ls -al video*
lrwxrwxrwx 1 root
root
6 Sep 23 14:59 video -> video0
crw------- 1 gorlando root
81, 0 Jan 28 2000 video0
crw------- 1 gorlando root
81, 1 Jan 28 2000 video1
The command "mknod"
You can create a new device on Linux running the command "mknod".
For example if you want to connect a third video camera, you need to
create a "new" device: "video2". Remember video0 is for the video camera
#1". Devices start from 0.
[root@ftosx1 /dev]# mknod /dev/video c 81 2
mknod: /dev/video: File exists
[root@ftosx1 /dev]# mknod /dev/video2 c 81 2
[root@ftosx1 /dev]# ls -al video*
lrwxrwxrwx 1 root
root
6 Sep 23 14:59 video -> video0
crw------- 1 gorlando root
81, 0 Jan 28 2000 video0
crw------- 1 gorlando root
81, 1 Jan 28 2000 video1
crw-r--r-- 1 root
root 81, 2 Feb 18 15:41 video2
[root@ftosx1 /dev]# l
If you write a new device driver for some special medical peripheral, and you want that Linux handle this device, then you (or the device mantainer) need to assign a number.
Like explained in the the files "devices.txt", the maximun number of devices for Linux is: 255.
Actual range number available for new devices is:
The old D.O.S. (Disk Operating System), the Windows 95/98/2000 VFAT, the original ext2, developed by Theodore T'so, the new ReiserFS, developed by Hans Reiser, the HFS for the Mac, the UFS for the latest MacOSX (beta), the old System V, the ISO9660 for the CD, the UDF for the DVD-R, ... are only some examples about the different filesystem types.
We present here the "Filesystem chapter" included in Linux Kernel 2.4.1:
You need to recompile the kernel or load the relative module to support a specific filesystem type. Is very important that you know all the filesystems type, because there are different and are everyday you must create, or mount or dump a specific filesystem.
When the system boots "mount" the hard disk, there is installed the Linux operating system in the directory "/" as we can see in the first line of the "/etc/fstab" file.
[root@heaven /root]# more /etc/fstab
/dev/hda3 / ext2 defaults 0 1
/proc /proc proc defaults 0 0
/dev/hda5 none swap defaults 0 0
#
/dev/fd0 /mnt/floppy ext2 defaults,noauto
0 0
#
/dev/hdb /mnt/cdrom iso9660 ro,noauto
0 0
/dev/hda1
/mnt/w95 msdos rw 0 2
/dev/hda2
/mnt/nt msdos rw 0 2
earth:/var/spool/fax
/mnt/earth nfs soft,bg,intr,nodev,nosuid,rw
0 0
[root@heaven /root]#
In this are listed all the File Systems that the system mounts in the start up process.
The device file representing blocks like floppy disks, hard disks, CD-ROMs, SCSI disks can be mounted at any time with the "mount" command.
For example, DVD-ROM media can be mounted on our CD-ROM SCSI unit, like a CD, with the command:
[root@heaven /root]# mount -t iso9660 /dev/sr0
/mnt/pd
mount: block device /dev/sr0 is write-protected,
mounting read-only
When we run the command "mount", we have to specify the File System type to mount: msdos, vfat, nfs, iso9660, etc. The device file that represents the hardware device on the system is the first SCSI CD-ROM, "/dev/sr0" and the mounting point on the system:
[root@heaven /root]# cd /mnt/pd
[root@heaven pd]# ls
audio_ts video_ts
[root@heaven pd]#
where we will find the information.
The DVD-ROM format of the last example is not supported at the moment on Linux. In the meantime, we use the ISO9660 format. This is the reason why we mount the DVD using the ISO9660 File system type.
This format allows you to have on average a higher capacity than on a CD-ROM!
In fact,running the command "disk free", "df", we obtain :
[root@heaven /root]# df -h
Filesystem
Size Used Avail Capacity Mounted on
/dev/hda3
4.7G 2.5G 2.0G 55%
/
/dev/hda1
1004M 106M 898M 11%
/mnt/w95
/dev/hda2
1004M 198M 805M 20%
/mnt/nt
/dev/sr0
7.7G 7.7G 0 100%
/mnt/pd
[root@heaven /root]#
Another command that belongs to the same family is the "disk usage" command, "du", that lets you find out how much space has been used on a disk or a single directory. For example, the device file uses a space of 51K :
[root@heaven /dev]# du -hs .
51K .
[root@heaven /dev]#
The directory "/etc" uses the following disk space:
[root@heaven /]# du -hs /etc
1.8M /etc
[root@heaven /]#
The option '-h' human readable is very useful. The option '-s' used with the program "du" allows to print only totals (the sum) of disk usage.
After installation, RedHat Linux makes two directories on "/mnt"
[root@heaven /root]# more /etc/fstab |
grep mnt
/dev/fd0 /mnt/floppy ext2 defaults,noauto
0 0
/dev/hdb /mnt/cdrom iso9660 ro,noauto
0 0
The word "noauto" means that the device will not be mounted during the boot phase.
Now, to mount a CD-ROM, the operation is very simple, you only have to run the command :
[root@heaven /root]# mount /mnt/cdrom
The command "mount" checks the File System table "/etc/fstab" and afterwards mounts the device.
The same is valid for a floppy whose type is "ext2" (Linux).
All these devices can be managed and mounted because there is a file system on the media. So, the CD-ROMs are written with a CD-writer that makes a file system of type iso9660 on the CD. DOS floppies can have a DOS filesystem simply by formatting the floppy in DR-DOS, PC-DOS, WINDOW 3.x, or others, and read on Linux.
To unmount a file system, you can run the command :
[root@heaven /root]# umount /mnt/cdrom
Before running the command "umount" it is necessary to verify that no users are logged in on the mounted file system. If you try to unmount the file system while a user is logged in, the "umount" command fails.
In any event, all the file systems are unmounted when the system shuts down.
The "mounting" situation can be listed by running the "mount" command without parameters.
[root@heaven /root]# mount
/dev/hda3 on / type ext2 (rw)
/proc on /proc type proc (rw)
/dev/hda1 on /mnt/w95 type msdos (rw)
/dev/hda2 on /mnt/nt type msdos (rw)
heaven:(pid446) on /auto type auto (intr,rw,port=1023,timeo=8,retrans=110,indirect,map=/etc/amd.localdev)
[root@heaven /root]#
All the File Systems mounted on the system are listed in the "/etc/mtab" file.
[root@heaven /root]# more /etc/mtab
/dev/hda3 / ext2 rw 0 1
/proc /proc proc rw 0 0
/dev/hda1 /mnt/w95 msdos rw 0 2
/dev/hda2 /mnt/nt msdos rw 0 2
heaven:(pid446) /auto auto intr,rw,port=1023,timeo=8,retrans=110,indirect,map=/etc/
amd.localdev 0 0
[root@heaven /root]#
For example if we your system support the ReiserFS, then you will see a screen like the following:
[root@ftosx1 base]# mount
/dev/hda2 on / type reiserfs (rw,notail)
none on /proc type proc (rw)
none on /dev/pts type devpts (rw,gid=5,mode=620)
automount(pid400) on /misc type autofs (rw,fd=5,pgrp=400,minproto=2,maxproto=3)
[root@ftosx1 base]#
