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SORT

Alex Costa — Sun, 04 Jan 2009 19:11:00 +0000

SORT(1) User Commands SORT(1)

NAME
sort – sort lines of text files

SYNOPSIS
sort [OPTION]… [FILE]…

DESCRIPTION
Write sorted concatenation of all FILE(s) to standard output.

Mandatory arguments to long options are mandatory for short options
too. Ordering options:

-b, –ignore-leading-blanks
ignore leading blanks

-d, –dictionary-order
consider only blanks and alphanumeric characters

-f, –ignore-case
fold lower case to upper case characters

-g, –general-numeric-sort
compare according to general numerical value

-i, –ignore-nonprinting
consider only printable characters

-M, –month-sort
compare (unknown) < `JAN’ < … < `DEC’

-n, –numeric-sort
compare according to string numerical value

-R, –random-sort
sort by random hash of keys

–random-source=FILE
get random bytes from FILE (default /dev/urandom)

–sort=WORD
sort according to WORD: general-numeric -g, month -M, numeric
-n, random -R

-r, –reverse
reverse the result of comparisons

Other options:

-c, –check, –check=diagnose-first
check for sorted input; do not sort

-C, –check=quiet, –check=silent
like -c, but do not report first bad line

–compress-program=PROG
compress temporaries with PROG; decompress them with PROG -d

-k, –key=POS1[,POS2]
start a key at POS1, end it at POS2 (origin 1)

-m, –merge
merge already sorted files; do not sort

-o, –output=FILE
write result to FILE instead of standard output

-s, –stable
stabilize sort by disabling last-resort comparison

-S, –buffer-size=SIZE
use SIZE for main memory buffer

-t, –field-separator=SEP
use SEP instead of non-blank to blank transition

-T, –temporary-directory=DIR
use DIR for temporaries, not $TMPDIR or /tmp; multiple options
specify multiple directories

-u, –unique
with -c, check for strict ordering; without -c, output only the
first of an equal run

-z, –zero-terminated
end lines with 0 byte, not newline

–help display this help and exit

–version
output version information and exit

POS is F[.C][OPTS], where F is the field number and C the character
position in the field; both are origin 1. If neither -t nor -b is in
effect, characters in a field are counted from the beginning of the
preceding whitespace. OPTS is one or more single-letter ordering
options, which override global ordering options for that key. If no
key is given, use the entire line as the key.

SIZE may be followed by the following multiplicative suffixes: % 1% of
memory, b 1, K 1024 (default), and so on for M, G, T, P, E, Z, Y.

With no FILE, or when FILE is -, read standard input.

*** WARNING *** The locale specified by the environment affects sort
order. Set LC_ALL=C to get the traditional sort order that uses native
byte values.

AUTHOR
Written by Mike Haertel and Paul Eggert.

REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.

COPYRIGHT
Copyright Â© 2008 Free Software Foundation, Inc. License GPLv3+: GNU
GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

SEE ALSO
The full documentation for sort is maintained as a Texinfo manual. If
the info and sort programs are properly installed at your site, the
command

info coreutils ‘sort invocation’

should give you access to the complete manual.

GNU coreutils 6.12 December 2008 SORT(1)

Technorati Tags: Linux Man Pages, SORT

January 1, 2009 -- MKDIRHIER
January 1, 2009 -- MODINFO
January 1, 2009 -- MKFS
January 1, 2009 -- MKNOD
January 1, 2009 -- MKSWAP

wvdial

Alex Costa — Fri, 02 Jan 2009 15:26:00 +0000

WVDIAL(1) WVDIAL(1)

NAME

wvdial – PPP dialer with built-in intelligence.

SYNOPSIS

DESCRIPTION

wvdial is an intelligent PPP dialer, which means that it dials a modem
and starts PPP in order to connect to the Internet. It is something
like the chat(8) program, except that it uses heuristics to guess how
to dial and log into your server rather than forcing you to write a
login script.

When wvdial starts, it first loads its configuration from
/etc/wvdial.conf and ~/.wvdialrc which contains basic information about
the modem port, speed, and init string, along with information about
your Internet Service Provider (ISP), such as the phone number, your
username, and your password.

Then it initializes your modem and dials the server and waits for a
connection (a CONNECT string from the modem). It understands and
responds to typical connection problems (like BUSY and NO DIALTONE).

Any time after connecting, wvdial will start PPP if it sees a PPP
sequence from the server. Otherwise, it tries to convince the server
to start PPP by doing the following:

– responding to any login/password prompts it sees;

– interpreting “choose one of the following”-style menus;

– eventually, sending the word “ppp” (a common terminal server com-
mand).

If all of this fails, wvdial just runs pppd(8) and hopes for the best.
It will bring up the connection, and then wait patiently for you to
drop the link by pressin CTRL-C.

OPTIONS

Several options are recognized by wvdial.

–chat Run wvdial as a chat replacement from within pppd, instead of
the more normal method of having wvdial negotiate the connection
and then call pppd.

–remotename
Override the Remote Name setting in the dialer configuration
section of the configuration file. This is mainly useful when
you dial to multiple systems with the same user name and pass-
word, and you don’t want to use inheritance to override this
setting (which is the recommended way to do it).

–config [configfile]
Run wvdial with configfile as the configuration file (instead of
/etc/wvdial.conf). This is mainly useful only if you want to
have per-user configurations, or you want to avoid having dial-
up information (usernames, passwords, calling card numbers,
etc.) in a system wide configuration file.

–no-syslog
Don’t output debug information to the syslog daemon (only useful
together with –chat).

–help Prints a short message describing how to use wvdial and exits.

–version
Displays wvdial’s version number and exits.

wvdial is normally run without command line options, in which case it
reads its configuration from the [Dialer Defaults] section of
/etc/wvdial.conf. (The configuration file is described in more detail
in wvdial.conf(5) manual page.)

One or more sections of /etc/wvdial.conf may be specified on the com-
mand line. Settings in these sections will override settings in
[Dialer Defaults].

For example, the command:
wvdial phone2

will read default options from the [Dialer Defaults] section, then
override any or all of the options with those found in the [Dialer
phone2] section.

If more than one section is specified, they are processed in the order
they are given. Each section will override all the sections that came
before it.

For example, the command:
wvdial phone2 pulse shh

will read default options from the [Dialer Defaults] section, then
override any or all of the options with those found in the [Dialer
phone2] section, followed by the [Dialer pulse] section, and lastly the
[Dialer shh] section.

Using this method, it is possible to easily configure wvdial to switch
between different internet providers, modem init strings, account
names, and so on without specifying the same configuration information
over and over.

BUGS

“Intelligent” programs are frustrating when they don’t work right.
This version of wvdial has only minimal support for disabling or over-
riding its “intelligence”, with the “Stupid Mode”, “Login Prompt”, and
“Password Prompt” options. So, in general if you have a nice ISP, it
will probably work, and if you have a weird ISP, it might not.

Still, it’s not much good if it doesn’t work for you, right? Don’t be
fooled by the fact that wvdial finally made it to version 1.00; it
could well contain many bugs and misfeatures. Let us know if you have
problems by sending e-mail to .

Also, there is now a mailing list for discussion about wvdial. If you
are having problems, or have anything else to say, send e-mail to
.

You may encounter some error messages if you don’t have write access to
/etc/ppp/pap-secrets and /etc/ppp/chap-secrets. Unfortunately, there’s
really no nice way around this yet.

FILES

/etc/wvdial.conf
Configuration file which contains modem, dialing, and login
information. See

/dev/ttyS*
Serial port devices.

/etc/ppp/peers/wvdial
Required for correct authentication in pppd version 2.3.0 or
newer.

/etc/ppp/{pap,chap}-secrets
Contains a list of usernames and passwords used by pppd for
authentication. wvdial maintains this list automatically.

AUTHORS

Dave Coombs and Avery Pennarun for Net Integration Technologies, as
part of the Worldvisions Weaver project. We would like to thank SuSE
and RedHat for adding a number of various cool features to Thanks guys!

MKDIRHIER

Alex Costa — Thu, 01 Jan 2009 19:11:00 +0000

MKDIRHIER(1) MKDIRHIER(1)

NAME
mkdirhier – makes a directory hierarchy

SYNOPSIS
mkdirhier directory …

DESCRIPTION
The mkdirhier command creates the specified directories. Unlike mkdir
if any of the parent directories of the specified directory do not
exist, it creates them as well.

MODINFO

Alex Costa — Thu, 01 Jan 2009 19:11:00 +0000

MODINFO(8) MODINFO(8)

NAME
modinfo – program to show information about a Linux Kernel module

SYNOPSIS
modinfo [ -0 ] [ -F field ] [ -k kernel ] [ modulename|filename ... ]

modinfo -V

modinfo -h

DESCRIPTION
modinfo extracts information from the Linux Kernel modules given on the
command line. If the module name is not a filename, then the /lib/mod-
ules/version directory is searched, as done by modprobe(8).

modinfo by default lists each attribute of the module in form fieldname
: value, for easy reading. The filename is listed the same way
(although it’s not really an attribute).

This version of modinfo can understand modules of any Linux Kernel
architecture.

OPTIONS
-V –version
Print the modinfo version. Note BACKWARDS COMPATIBILITY below:
you might be printing the version of modinfo.old.

-F –field
Only print this field value, one per line. This is most useful
for scripts. Field names are case-insenitive. Common fields
(which may not be in every module) include author, description,
license, param, depends, and alias. There are often multiple
param, alias and depends fields. The special field filename
lists the filename of the module.

-k kernel
Provide information about a kernel other than the running one.
This is particularly useful for distributions needing to extract
information from a newly installed (but not yet running) set of
kernel modules. For example, you wish to find which firmware
files are needed by various modules in a new kernel for which
you must make an initrd image prior to booting.

-0 –null
Use the ASCII zero character to separate field values, instead
of a new line. This is useful for scripts, since a new line can
theoretically appear inside a field.

-a -d -l -p -n
These are shortcuts for author, description, license. param and
filename respectively, to ease the transition from the old modu-
tils modinfo.

BACKWARDS COMPATIBILITY
This version of modinfo is for kernel modules 2.5.48 and above. If it
detects a kernel with support for old-style modules, it will attempt to
run modprobe.old in its place, so it is completely transparent to the
user.

Note that the output of this version of modinfo is simpler and more
regular than the older version: scripts attempting to use the default
output may get confused with complex fields.

You can force the new modinfo to always be used, by setting the
NEW_MODINFO environment variable.

MKFS

Alex Costa — Thu, 01 Jan 2009 19:11:00 +0000

MKFS(8) MKFS(8)

NAME
mkfs – build a Linux file system

SYNOPSIS
mkfs [ -V ] [ -t fstype ] [ fs-options ] filesys [ blocks ]

DESCRIPTION
mkfs is used to build a Linux file system on a device, usually a hard
disk partition. filesys is either the device name (e.g. /dev/hda1,
/dev/sdb2). blocks is the number of blocks to be used for the file
system.

The exit code returned by mkfs is 0 on success and 1 on failure.

In actuality, mkfs is simply a front-end for the various file system
builders (mkfs.fstype) available under Linux. The file system-specific
builder is searched for in a number of directories like perhaps /sbin,
/sbin/fs, /sbin/fs.d, /etc/fs, /etc (the precise list is defined at
compile time but at least contains /sbin and /sbin/fs), and finally in
the directories listed in the PATH environment variable. Please see
the file system-specific builder manual pages for further details.

OPTIONS
-V Produce verbose output, including all file system-specific com-
mands that are executed. Specifying this option more than once
inhibits execution of any file system-specific commands. This
is really only useful for testing.

-t fstype
Specifies the type of file system to be built. If not speci-
fied, the default file system type (currently ext2) is used.

fs-options
File system-specific options to be passed to the real file sys-
tem builder. Although not guaranteed, the following options are
supported by most file system builders.

-c Check the device for bad blocks before building the file system.

-l filename
Read the bad blocks list from filename

-v Produce verbose output.

BUGS
All generic options must precede and not be combined with file system-
specific options. Some file system-specific programs do not support
the -v (verbose) option, nor return meaningful exit codes. Also, some
file system-specific programs do not automatically detect the device
size and require the blocks parameter to be specified.

AUTHORS
David Engel (david@ods.com)
Fred N. van Kempen (waltje@uwalt.nl.mugnet.org)
Ron Sommeling (sommel@sci.kun.nl)
The manual page was shamelessly adapted from Remy Card’s version for
the ext2 file system.

SEE ALSO
fs(5), badblocks(8), fsck(8), mkdosfs(8), mke2fs(8), mkfs.bfs(8),
mkfs.ext2(8), mkfs.ext3(8), mkfs.minix(8), mkfs.msdos(8), mkfs.vfat(8),
mkfs.xfs(8), mkfs.xiafs(8)

AVAILABILITY
The mkfs command is part of the util-linux-ng package and is available
from ftp://ftp.kernel.org/pub/linux/utils/util-linux-ng/.

Version 1.9 Jun 1995 MKFS(8)

Technorati Tags: Linux Man Pages, MKFS

January 4, 2009 -- SORT
January 1, 2009 -- MKDIRHIER
January 1, 2009 -- MODINFO
January 1, 2009 -- MKNOD
January 1, 2009 -- MKSWAP

MKNOD

Alex Costa — Thu, 01 Jan 2009 19:11:00 +0000

MKNOD(1) User Commands MKNOD(1)

NAME
mknod – make block or character special files

SYNOPSIS
mknod [OPTION]… NAME TYPE [MAJOR MINOR]

DESCRIPTION
Create the special file NAME of the given TYPE.

-Z, –context=CTX
set the SELinux security context of NAME to CTX

Mandatory arguments to long options are mandatory for short options
too.

-m, –mode=MODE
set file permission bits to MODE, not a=rw – umask

–help display this help and exit

–version
output version information and exit

Both MAJOR and MINOR must be specified when TYPE is b, c, or u, and
they must be omitted when TYPE is p. If MAJOR or MINOR begins with 0x
or 0X, it is interpreted as hexadecimal; otherwise, if it begins with
0, as octal; otherwise, as decimal. TYPE may be:

b create a block (buffered) special file

c, u create a character (unbuffered) special file

p create a FIFO

NOTE: your shell may have its own version of mknod, which usually
supersedes the version described here. Please refer to your shell’s
documentation for details about the options it supports.

AUTHOR
Written by David MacKenzie.

REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.

MKSWAP

Alex Costa — Thu, 01 Jan 2009 19:11:00 +0000

MKSWAP(8) Linux Programmer’s Manual MKSWAP(8)

NAME
mkswap – set up a Linux swap area

SYNOPSIS
mkswap [-c] [-vN] [-f] [-p PSZ] [-L label] [-U uuid] device [size]

DESCRIPTION
mkswap sets up a Linux swap area on a device or in a file.

(After creating the swap area, you need the swapon command to start
using it. Usually swap areas are listed in /etc/fstab so that they can
be taken into use at boot time by a swapon -a command in some boot
script.)

The device argument will usually be a disk partition (something like
/dev/hda4 or /dev/sdb7) but can also be a file. The Linux kernel does
not look at partition Id’s, but many installation scripts will assume
that partitions of hex type 82 (LINUX_SWAP) are meant to be swap parti-
tions. (Warning: Solaris also uses this type. Be careful not to kill
your Solaris partitions.)

The size parameter is superfluous but retained for backwards compati-
bility. (It specifies the desired size of the swap area in 1024-byte
blocks. mkswap will use the entire partition or file if it is omitted.
Specifying it is unwise – a typo may destroy your disk.)

The PSZ parameter specifies the page size to use. It is almost always
unnecessary (even unwise) to specify it, but certain old libc versions
lie about the page size, so it is possible that mkswap gets it wrong.
The symptom is that a subsequent swapon fails because no swap signature
is found. Typical values for PSZ are 4096 or 8192.

Linux knows about two styles of swap areas, old style and new style.
The last 10 bytes of the first page of the swap area distinguishes
them: old style has `SWAP_SPACE’, new style has `SWAPSPACE2′ as signa-
ture.

In the old style, the rest of this first page was a bit map, with a 1
bit for each usable page of the swap area. Since the first page holds
this bit map, the first bit is 0. Also, the last 10 bytes hold the
signature. So, if the page size is S, an old style swap area can
describe at most 8*(S-10)-1 pages used for swapping. With S=4096 (as
on i386), the useful area is at most 133890048 bytes (almost 128 MiB),
and the rest is wasted. On an alpha and sparc64, with S=8192, the use-
ful area is at most 535560992 bytes (almost 512 MiB).

The old setup wastes most of this bitmap page, because zero bits denote
bad blocks or blocks past the end of the swap space, and a simple inte-
ger suffices to indicate the size of the swap space, while the bad
blocks, if any, can simply be listed. Nobody wants to use a swap space
with hundreds of bad blocks. (I would not even use a swap space with 1
bad block.) In the new style swap area this is precisely what is done.

The maximum useful size of a swap area depends on the architecture and
the kernel version. It is roughly 2GiB on i386, PPC, m68k, ARM, 1GiB
on sparc, 512MiB on mips, 128GiB on alpha and 3TiB on sparc64. For ker-
nels after 2.3.3 there is no such limitation.

Note that before 2.1.117 the kernel allocated one byte for each page,
while it now allocates two bytes, so that taking a swap area of 2 GiB
in use might require 2 MiB of kernel memory.

Presently, Linux allows 32 swap areas (this was 8 before Linux 2.4.10).
The areas in use can be seen in the file /proc/swaps (since 2.1.25).

mkswap refuses areas smaller than 10 pages.

If you don’t know the page size that your machine uses, you may be able
to look it up with “cat /proc/cpuinfo” (or you may not – the contents
of this file depend on architecture and kernel version).

To setup a swap file, it is necessary to create that file before ini-
tializing it with mkswap , e.g. using a command like

# dd if=/dev/zero of=swapfile bs=1024 count=65536

Note that a swap file must not contain any holes (so, using cp(1) to
create the file is not acceptable).

OPTIONS
-c Check the device (if it is a block device) for bad blocks before
creating the swap area. If any are found, the count is printed.

-f Force – go ahead even if the command is stupid. This allows the
creation of a swap area larger than the file or partition it
resides on. On SPARC, force creation of the swap area. Without
this option mkswap will refuse to create a v0 swap on a device
with a valid SPARC superblock, as that probably means one is
going to erase the partition table.

-p PSZ Specify the page size to use.

-L label
Specify a label, to allow swapon by label. (Only for new style
swap areas.)

-v0 Create an old style swap area.

-v1 Create a new style swap area.

If no -v option is given, mkswap will default to new style, but use old
style if the current kernel is older than 2.1.117 (and also if
PAGE_SIZE is less than 2048). The new style header does not touch the
first block, so may be preferable, in case you have a boot loader or
disk label there. If you need to use both 2.0 and 2.2 kernels, use the
-v0 option when creating the swapspace.

Version 0 (-v0) swap space format is no longer supported in 2.5+ ker-
nels.

-U uuid
Specify the uuid to use. The default is to generate UUIDs.

MV

Alex Costa — Thu, 01 Jan 2009 19:11:00 +0000

MV(1) User Commands MV(1)

NAME
mv – move (rename) files

SYNOPSIS
mv [OPTION]… [-T] SOURCE DEST
mv [OPTION]… SOURCE… DIRECTORY
mv [OPTION]… -t DIRECTORY SOURCE…

DESCRIPTION
Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY.

Mandatory arguments to long options are mandatory for short options
too.

–backup[=CONTROL]
make a backup of each existing destination file

-b like –backup but does not accept an argument

-f, –force
do not prompt before overwriting

-i, –interactive
prompt before overwrite

–strip-trailing-slashes
remove any trailing slashes from each SOURCE argument

-S, –suffix=SUFFIX
override the usual backup suffix

-t, –target-directory=DIRECTORY
move all SOURCE arguments into DIRECTORY

-T, –no-target-directory
treat DEST as a normal file

-u, –update
move only when the SOURCE file is newer than the destination
file or when the destination file is missing

-v, –verbose
explain what is being done

–help display this help and exit

–version
output version information and exit

The backup suffix is `~’, unless set with –suffix or SIM-
PLE_BACKUP_SUFFIX. The version control method may be selected via the
–backup option or through the VERSION_CONTROL environment variable.
Here are the values:

none, off
never make backups (even if –backup is given)

numbered, t
make numbered backups

existing, nil
numbered if numbered backups exist, simple otherwise

simple, never
always make simple backups

AUTHOR
Written by Mike Parker, David MacKenzie, and Jim Meyering.

REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.

MODPROBE

Alex Costa — Thu, 01 Jan 2009 19:11:00 +0000

MODPROBE(8) MODPROBE(8)

NAME
modprobe – program to add and remove modules from the Linux Kernel

SYNOPSIS
modprobe [ -v ] [ -V ] [ -C config-file ] [ -n ] [ -i ] [ -q ] [ -o
modulename ] [ modulename ] [ module parameters ... ]

modprobe [ -r ] [ -v ] [ -n ] [ -i ] [ modulename ... ]

modprobe [ -l ] [ -t dirname ] [ wildcard ]

modprobe [ -c ]

modprobe [ --dump-modversions ]

DESCRIPTION
modprobe intelligently adds or removes a module from the Linux kernel:
note that for convenience, there is no difference between _ and – in
module names. modprobe looks in the module directory /lib/mod-
ules/`uname -r` for all the modules and other files, except for the
optional /etc/modprobe.conf configuration file and /etc/modprobe.d
directory (see modprobe.conf(5)). modprobe will also use module options
specified on the kernel command line in the form of .option>.

Note that this version of modprobe does not do anything to the module
itself: the work of resolving symbols and understanding parameters is
done inside the kernel. So module failure is sometimes accompanied by
a kernel message: see dmesg(8).

modprobe expects an up-to-date modules.dep file, as generated by depmod
(see depmod(8)). This file lists what other modules each module needs
(if any), and modprobe uses this to add or remove these dependencies
automatically. See modules.dep(5)).

If any arguments are given after the modulename, they are passed to the
kernel (in addition to any options listed in the configuration file).

OPTIONS
-v –verbose
Print messages about what the program is doing. Usually mod-
probe only prints messages if something goes wrong.

This option is passed through install or remove commands to
other modprobe commands in the MODPROBE_OPTIONS environment
variable.

-C –config
This option overrides the default configuration file (/etc/mod-
probe.conf or /etc/modprobe.d/ if that isn’t found).

This option is passed through install or remove commands to
other modprobe commands in the MODPROBE_OPTIONS environment
variable.

-c –showconfig
Dump out the configuration file and exit.

-n –dry-run
This option does everything but actually insert or delete the
modules (or run the install or remove commands). Combined with
-v, it is useful for debugging problems.

-i –ignore-install –ignore-remove
This option causes modprobe to ignore install and remove com-
mands in the configuration file (if any), for the module on the
command line (any dependent modules are still subject to com-
mands set for them in the configuration file). See mod-
probe.conf(5).

-q –quiet
Normally modprobe will report an error if you try to remove or
insert a module it can’t find (and isn’t an alias or
install/remove command). With this flag, modprobe will simply
ignore any bogus names (the kernel uses this to opportunisti-
cally probe for modules which might exist).

-r –remove
This option causes modprobe to remove, rather than insert a mod-
ule. If the modules it depends on are also unused, modprobe
will try to remove them, too. Unlike insertion, more than one
module can be specified on the command line (it does not make
sense to specify module parameters when removing modules).

There is usually no reason to remove modules, but some buggy
modules require it. Your kernel may not support removal of mod-
ules.

-w –wait
This option is applicable only with the -r or –remove option.
It causes modprobe to block in the kernel (within the kernel
module handling code itself) waiting for the specified modules’
reference count to reach zero. Default operation is for modprobe
to operate like rmmod, which exits with EWOULDBLOCK if the mod-
ules reference count is non-zero.

-V –version
Show version of program, and exit. See below for caveats when
run on older kernels.

-f –force
Try to strip any versioning information from the module, which
might otherwise stop it from loading: this is the same as using
both –force-vermagic and –force-modversion. Naturally, these
checks are there for your protection, so using this option is
dangerous.

This applies to any modules inserted: both the module (or alias)
on the command line, and any modules it depends on.

–force-vermagic
Every module contains a small string containing important infor-
mation, such as the kernel and compiler versions. If a module
fails to load and the kernel complains that the “version magic”
doesn’t match, you can use this option to remove it. Naturally,
this check is there for your protection, so this using option is
dangerous.

This applies to any modules inserted: both the module (or alias)
on the command line, and any modules it depends on.

–force-modversion
When modules are compiled with CONFIG_MODVERSIONS set, a section
is created detailing the versions of every interface used by (or
supplied by) the module. If a module fails to load and the ker-
nel complains that the module disagrees about a version of some
interface, you can use “–force-modversion” to remove the ver-
sion information altogether. Naturally, this check is there for
your protection, so using this option is dangerous.

This applies any modules inserted: both the module (or alias) on
the command line, and any modules it depends on.

-l –list
List all modules matching the given wildcard (or “*” if no wild-
card is given). This option is provided for backwards compati-
bility: see find(1) and basename(1) for a more flexible alterna-
tive.

-a –all
Insert all module names on the command line.

-t –type
Restrict -l to modules in directories matching the dirname
given. This option is provided for backwards compatibility: see
find(1) and basename(1) or a more flexible alternative.

-s –syslog
This option causes any error messages to go through the syslog
mechanism (as LOG_DAEMON with level LOG_NOTICE) rather than to
standard error. This is also automatically enabled when stderr
is unavailable.

This option is passed through install or remove commands to
other modprobe commands in the MODPROBE_OPTIONS environment
variable.

–set-version
Set the kernel version, rather than using uname(2) to decide on
the kernel version (which dictates where to find the modules).
This also disables backwards compatibility checks (so mod-
probe.old(8) will never be run).

–show-depends
List the dependencies of a module (or alias), including the mod-
ule itself. This produces a (possibly empty) set of module
filenames, one per line, each starting with “insmod”. Install
commands which apply are shown prefixed by “install”. It does
not run any of the install commands. Note that modinfo(8) can
be used to extract dependencies of a module from the module
itself, but knows nothing of aliases or install commands.

-o –name
This option tries to rename the module which is being inserted
into the kernel. Some testing modules can usefully be inserted
multiple times, but the kernel refuses to have two modules of
the same name. Normally, modules should not require multiple
insertions, as that would make them useless if there were no
module support.

–first-time
Normally, modprobe will succeed (and do nothing) if told to
insert a module which is already present, or remove a module
which isn’t present. This is backwards compatible with the
modutils, and ideal for simple scripts. However, more compli-
cated scripts often want to know whether modprobe really did
something: this option makes modprobe fail for that case.

–dump-modversions
Print out a list of module versioning information required by a
module. This option is commonly used by distributions in order
to package up a Linuxx kernel module using module versioning
deps.

–use-blacklist
Apply a matchin blacklist entry also to a request by module
name, not only to a request by an alias.

–allow-unsupported-modules
Load unsupported modules even if disabled in configuration.

RETURN VALUE
modprobe returns 0 on success, 1 on an unspecified error and 2 if the
module is not supported. Use the –allow-unsupported-modules option to
force using an unsupported module.

BACKWARDS COMPATIBILITY
This version of modprobe is for kernels 2.5.48 and above. If it
detects a kernel with support for old-style modules (for which much of
the work was done in userspace), it will attempt to run modprobe.old in
its place, so it is completely transparent to the user.

ENVIRONMENT
The MODPROBE_OPTIONS environment variable can also be used to pass
arguments to modprobe.

SEE ALSO
modprobe.conf(5), lsmod(8), modprobe.old(8)

01 December 2008 MODPROBE(8)

Technorati Tags: Linux Man Pages, MODPROBE

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DATE

Alex Costa — Thu, 01 Jan 2009 17:20:00 +0000

DATE(1) User Commands DATE(1)

NAME
date – print or set the system date and time

SYNOPSIS
date [OPTION]… [+FORMAT]
date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]

DESCRIPTION
Display the current time in the given FORMAT, or set the system date.

-d, –date=STRING
display time described by STRING, not `now’

-f, –file=DATEFILE
like –date once for each line of DATEFILE

-r, –reference=FILE
display the last modification time of FILE

-R, –rfc-2822
output date and time in RFC 2822 format. Example: Mon, 07 Aug
2006 12:34:56 -0600

–rfc-3339=TIMESPEC
output date and time in RFC 3339 format. TIMESPEC=`date’, `sec-
onds’, or `ns’ for date and time to the indicated precision.
Date and time components are separated by a single space:
2006-08-07 12:34:56-06:00

-s, –set=STRING
set time described by STRING

-u, –utc, –universal
print or set Coordinated Universal Time

–help display this help and exit

–version
output version information and exit

FORMAT controls the output. The only valid option for the second form
specifies Coordinated Universal Time. Interpreted sequences are:

%% a literal %

%a locale’s abbreviated weekday name (e.g., Sun)

%A locale’s full weekday name (e.g., Sunday)

%b locale’s abbreviated month name (e.g., Jan)

%B locale’s full month name (e.g., January)

%c locale’s date and time (e.g., Thu Mar 3 23:05:25 2005)

%C century; like %Y, except omit last two digits (e.g., 21)

%d day of month (e.g, 01)

%D date; same as %m/%d/%y

%e day of month, space padded; same as %_d

%F full date; same as %Y-%m-%d

%g last two digits of year of ISO week number (see %G)

%G year of ISO week number (see %V); normally useful only with %V

%h same as %b

%H hour (00..23)

%I hour (01..12)

%j day of year (001..366)

%k hour ( 0..23)

%l hour ( 1..12)

%m month (01..12)

%M minute (00..59)

%n a newline

%N nanoseconds (000000000..999999999)

%p locale’s equivalent of either AM or PM; blank if not known

%P like %p, but lower case

%r locale’s 12-hour clock time (e.g., 11:11:04 PM)

%R 24-hour hour and minute; same as %H:%M

%s seconds since 1970-01-01 00:00:00 UTC

%S second (00..60)

%t a tab

%T time; same as %H:%M:%S

%u day of week (1..7); 1 is Monday

%U week number of year, with Sunday as first day of week (00..53)

%V ISO week number, with Monday as first day of week (01..53)

%w day of week (0..6); 0 is Sunday

%W week number of year, with Monday as first day of week (00..53)

%x locale’s date representation (e.g., 12/31/99)

%X locale’s time representation (e.g., 23:13:48)

%y last two digits of year (00..99)

%Y year

%z +hhmm numeric timezone (e.g., -0400)

%:z +hh:mm numeric timezone (e.g., -04:00)

%::z +hh:mm:ss numeric time zone (e.g., -04:00:00)

%:::z numeric time zone with : to necessary precision (e.g., -04,
+05:30)

%Z alphabetic time zone abbreviation (e.g., EDT)

By default, date pads numeric fields with zeroes. The following
optional flags may follow `%’:

– (hyphen) do not pad the field

_ (underscore) pad with spaces

0 (zero) pad with zeros

^ use upper case if possible

# use opposite case if possible

After any flags comes an optional field width, as a decimal number;
then an optional modifier, which is either E to use the locale’s alter-
nate representations if available, or O to use the locale’s alternate
numeric symbols if available.

DATE STRING
The –date=STRING is a mostly free format human readable date string
such as “Sun, 29 Feb 2004 16:21:42 -0800″ or “2004-02-29 16:21:42″ or
even “next Thursday”. A date string may contain items indicating cal-
endar date, time of day, time zone, day of week, relative time, rela-
tive date, and numbers. An empty string indicates the beginning of the
day. The date string format is more complex than is easily documented
here but is fully described in the info documentation.

AUTHOR
Written by David MacKenzie.

REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.

SEE ALSO
The full documentation for date is maintained as a Texinfo manual. If
the info and date programs are properly installed at your site, the
command

info coreutils ‘date invocation’

should give you access to the complete manual.

GNU coreutils 6.12 May 2008 DATE(1)

Technorati Tags: DATE, Linux Man Pages

January 31, 2011 -- It is not safe to rely on the system’s timezone settings
January 4, 2009 -- SORT
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January 1, 2009 -- MKFS

DD

Alex Costa — Thu, 01 Jan 2009 17:20:00 +0000

DD(1) User Commands DD(1)

NAME
dd – convert and copy a file

SYNOPSIS
dd [OPERAND]…
dd OPTION

DESCRIPTION
Copy a file, converting and formatting according to the operands.

bs=BYTES
force ibs=BYTES and obs=BYTES

cbs=BYTES
convert BYTES bytes at a time

conv=CONVS
convert the file as per the comma separated symbol list

count=BLOCKS
copy only BLOCKS input blocks

ibs=BYTES
read BYTES bytes at a time

if=FILE
read from FILE instead of stdin

iflag=FLAGS
read as per the comma separated symbol list

obs=BYTES
write BYTES bytes at a time

of=FILE
write to FILE instead of stdout

oflag=FLAGS
write as per the comma separated symbol list

seek=BLOCKS
skip BLOCKS obs-sized blocks at start of output

skip=BLOCKS
skip BLOCKS ibs-sized blocks at start of input

status=noxfer
suppress transfer statistics

BLOCKS and BYTES may be followed by the following multiplicative suf-
fixes: xM M, c 1, w 2, b 512, kB 1000, K 1024, MB 1000*1000, M
1024*1024, GB 1000*1000*1000, G 1024*1024*1024, and so on for T, P, E,
Z, Y.

Each CONV symbol may be:

ascii from EBCDIC to ASCII

ebcdic from ASCII to EBCDIC

ibm from ASCII to alternate EBCDIC

block pad newline-terminated records with spaces to cbs-size

unblock
replace trailing spaces in cbs-size records with newline

lcase change upper case to lower case

nocreat
do not create the output file

excl fail if the output file already exists

notrunc
do not truncate the output file

ucase change lower case to upper case

swab swap every pair of input bytes

noerror
continue after read errors

sync pad every input block with NULs to ibs-size; when used with
block or unblock, pad with spaces rather than NULs

fdatasync
physically write output file data before finishing

fsync likewise, but also write metadata

Each FLAG symbol may be:

append append mode (makes sense only for output; conv=notrunc sug-
gested)

direct use direct I/O for data

directory fail unless a directory dsync use synchronized I/O
for data sync likewise, but also for metadata nonblock use
non-blocking I/O noatime do not update access time noctty
do not assign controlling terminal from file nofollow do not
follow symlinks

Sending a USR1 signal to a running `dd’ process makes it print I/O
statistics to standard error and then resume copying.

$ dd if=/dev/zero of=/dev/null& pid=$!
$ kill -USR1 $pid; sleep 1; kill $pid

18335302+0 records in 18335302+0 records out 9387674624 bytes
(9.4 GB) copied, 34.6279 seconds, 271 MB/s

Options are:

–help display this help and exit

–version
output version information and exit

AUTHOR
Written by Paul Rubin, David MacKenzie, and Stuart Kemp.

REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.

SEE ALSO
The full documentation for dd is maintained as a Texinfo manual. If
the info and dd programs are properly installed at your site, the com-
mand

info coreutils ‘dd invocation’

should give you access to the complete manual.

GNU coreutils 6.12 May 2008 DD(1)

Technorati Tags: DD, Linux Ma Pages

January 1, 2009 -- INFO

DEPMOD

Alex Costa — Thu, 01 Jan 2009 17:20:00 +0000

DEPMOD(8) DEPMOD(8)

NAME
depmod – program to generate modules.dep and map files.

SYNOPSIS
depmod [ -b basedir ] [ -e ] [ -F System.map ] [ -n ] [ -v ] [ version
] [ -A ]

depmod [ -e ] [ -FSystem.map ] [ -n ] [ -v ] [ version ] [ filename ...
]

DESCRIPTION
Linux kernel modules can provide services (called “symbols”) for other
modules to use (using EXPORT_SYMBOL in the code). If a second module
uses this symbol, that second module clearly depends on the first mod-
ule. These dependencies can get quite complex.

depmod creates a list of module dependencies, by reading each module
under /lib/modules/version and determining what symbols it exports, and
what symbols it needs. By default this list is written to modules.dep
in the same directory. If filenames are given on the command line,
only those modules are examined (which is rarely useful, unless all
modules are listed).

If a version is provided, then that kernel version’s module directory
is used, rather than the current kernel version (as returned by “uname
-r”).

depmod will also generate various map files in this directory, for use
by the hotplug infrastructure.

OPTIONS
-a –all
Probe all modules. This option is enabled by default if no file
names are given in the command-line.

-A –quick
This option scans to see if any modules are newer than the mod-
ules.dep file before any work is done: if not, it silently exits
rather than regenerating the files.

-b basedir –basedir basedir
If your modules are not currently in the (normal) directory
/lib/modules/version, but in a staging area, you can specify a
basedir which is prepended to the directory name. This basedir
is stripped from the resulting modules.dep file, so it is ready
to be moved into the normal location.

-C –config file or directory
This option overrides the default configuration file (/etc/dep-
mod.conf or /etc/depmod.d/ if that is not found).

-e –errsyms
When combined with the -F option, this reports any symbols which
a module needs which are not supplied by other modules or the
kernel. Normally, any symbols not provided by modules are
assumed to be provided by the kernel (which should be true in a
perfect world).

-F –filesyms System.map
Supplied with the System.map produced when the kernel was built,
this allows the -e option to report unresolved symbols.

-h –help
Print the help message, and exit.

-n –dry-run
This sends the resulting modules.dep, then the various map
files, to standard output, rather than writing them into the
module directory.

-v –verbose
In verbose mode depmod will print (to stdout) all the symbols
each module depends on and the module’s file name which provides
that symbol.

-V –version
Show version of program, and exit. See below for caveats when
run on older kernels.

BACKWARDS COMPATIBILITY
This version of depmod is for kernels 2.5.48 and above. If it detects
a kernel with support for old-style modules, or the version specified
is before 2.5.48, it will attempt to run depmod.old in its place, so it
is completely transparent to the user.

SEE ALSO
modprobe(8), modules.dep(5), depmod.old(8)

22 August 2008 DEPMOD(8)

Technorati Tags: DEPMOD, Linux Man Pages

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DF

Alex Costa — Thu, 01 Jan 2009 17:20:00 +0000

DF(1) User Commands DF(1)

NAME
df – report file system disk space usage

SYNOPSIS
df [OPTION]… [FILE]…

DESCRIPTION
This manual page documents the GNU version of df. df displays the
amount of disk space available on the file system containing each file
name argument. If no file name is given, the space available on all
currently mounted file systems is shown. Disk space is shown in 1K
blocks by default, unless the environment variable POSIXLY_CORRECT is
set, in which case 512-byte blocks are used.

If an argument is the absolute file name of a disk device node contain-
ing a mounted file system, df shows the space available on that file
system rather than on the file system containing the device node (which
is always the root file system). This version of df cannot show the
space available on unmounted file systems, because on most kinds of
systems doing so requires very nonportable intimate knowledge of file
system structures.

OPTIONS
Show information about the file system on which each FILE resides, or
all file systems by default.

Mandatory arguments to long options are mandatory for short options
too.

-a, –all
include dummy file systems

-B, –block-size=SIZE
use SIZE-byte blocks

-h, –human-readable
print sizes in human readable format (e.g., 1K 234M 2G)

-H, –si
likewise, but use powers of 1000 not 1024

-i, –inodes
list inode information instead of block usage

-k like –block-size=1K

-l, –local
limit listing to local file systems

–no-sync
do not invoke sync before getting usage info (default)

-P, –portability
use the POSIX output format

–sync invoke sync before getting usage info

-t, –type=TYPE
limit listing to file systems of type TYPE

-T, –print-type
print file system type

-x, –exclude-type=TYPE
limit listing to file systems not of type TYPE

-v (ignored)

–help display this help and exit

–version
output version information and exit

SIZE may be (or may be an integer optionally followed by) one of fol-
lowing: kB 1000, K 1024, MB 1000*1000, M 1024*1024, and so on for G, T,
P, E, Z, Y.

AUTHOR
Written by Torbj?rn Granlund, David MacKenzie, and Paul Eggert.

REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.

SEE ALSO
The full documentation for df is maintained as a Texinfo manual. If
the info and df programs are properly installed at your site, the com-
mand

info coreutils ‘df invocation’

should give you access to the complete manual.

GNU coreutils 6.12 May 2008 DF(1)

Technorati Tags: DF, Linux Man Pages

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DIFF

Alex Costa — Thu, 01 Jan 2009 17:20:00 +0000

DIFF(1) User Commands DIFF(1)

NAME
diff – compare files line by line

SYNOPSIS
diff [OPTION]… FILES

DESCRIPTION
Compare files line by line.

-i –ignore-case
Ignore case differences in file contents.

–ignore-file-name-case
Ignore case when comparing file names.

–no-ignore-file-name-case
Consider case when comparing file names.

-E –ignore-tab-expansion
Ignore changes due to tab expansion.

-b –ignore-space-change
Ignore changes in the amount of white space.

-w –ignore-all-space
Ignore all white space.

-B –ignore-blank-lines
Ignore changes whose lines are all blank.

-I RE –ignore-matching-lines=RE
Ignore changes whose lines all match RE.

–strip-trailing-cr
Strip trailing carriage return on input.

-a –text
Treat all files as text.

-c -C NUM –context[=NUM]
Output NUM (default 3) lines of copied context.

-u -U NUM –unified[=NUM]
Output NUM (default 3) lines of unified context.

–label LABEL
Use LABEL instead of file name.

-p –show-c-function
Show which C function each change is in.

-F RE –show-function-line=RE
Show the most recent line matching RE.

-q –brief
Output only whether files differ.

-e –ed
Output an ed script.

–normal
Output a normal diff.

-n –rcs
Output an RCS format diff.

-y –side-by-side
Output in two columns.

-W NUM –width=NUM
Output at most NUM (default 130) print columns.

–left-column
Output only the left column of common lines.

–suppress-common-lines
Do not output common lines.

-D NAME –ifdef=NAME
Output merged file to show `#ifdef NAME’ diffs.

–GTYPE-group-format=GFMT
Similar, but format GTYPE input groups with GFMT.

–line-format=LFMT
Similar, but format all input lines with LFMT.

–LTYPE-line-format=LFMT
Similar, but format LTYPE input lines with LFMT.

LTYPE is `old’, `new’, or `unchanged’.
GTYPE is LTYPE or `changed’.

GFMT may contain:

%< lines from FILE1

%> lines from FILE2

%= lines common to FILE1 and FILE2

%[-][WIDTH][.[PREC]]{doxX}LETTER
printf-style spec for LETTER

LETTERs are as follows for new group, lower case for old group:

F first line number

L last line number

N number of lines = L-F+1

E F-1

M L+1

LFMT may contain:

%L contents of line

%l contents of line, excluding any trailing newline

%[-][WIDTH][.[PREC]]{doxX}n
printf-style spec for input line number

Either GFMT or LFMT may contain:

%% %

%c’C’ the single character C

%c’\OOO’
the character with octal code OOO

-l –paginate
Pass the output through `pr’ to paginate it.

-t –expand-tabs
Expand tabs to spaces in output.

-T –initial-tab
Make tabs line up by prepending a tab.

–tabsize=NUM
Tab stops are every NUM (default 8) print columns.

–suppress-blank-empty
Suppress space or tab before empty output lines.

-r –recursive
Recursively compare any subdirectories found.

-N –new-file
Treat absent files as empty.

–unidirectional-new-file
Treat absent first files as empty.

-s –report-identical-files
Report when two files are the same.

-x PAT –exclude=PAT
Exclude files that match PAT.

-X FILE –exclude-from=FILE
Exclude files that match any pattern in FILE.

-S FILE –starting-file=FILE
Start with FILE when comparing directories.

–from-file=FILE1
Compare FILE1 to all operands. FILE1 can be a directory.

–to-file=FILE2
Compare all operands to FILE2. FILE2 can be a directory.

–horizon-lines=NUM
Keep NUM lines of the common prefix and suffix.

-d –minimal
Try hard to find a smaller set of changes.

–speed-large-files
Assume large files and many scattered small changes.

-v –version
Output version info.

–help Output this help.

FILES are `FILE1 FILE2′ or `DIR1 DIR2′ or `DIR FILE…’ or `FILE…
DIR’. If –from-file or –to-file is given, there are no restrictions
on FILES. If a FILE is `-’, read standard input. Exit status is 0 if
inputs are the same, 1 if different, 2 if trouble.

AUTHOR
Written by Paul Eggert, Mike Haertel, David Hayes, Richard Stallman,
and Len Tower.

REPORTING BUGS
Report bugs to <bug-gnu-utils@gnu.org>.

COPYRIGHT
Copyright Â© 2007 Free Software Foundation, Inc. License GPLv3+: GNU
GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

SEE ALSO
The full documentation for diff is maintained as a Texinfo manual. If
the info and diff programs are properly installed at your site, the
command

info diff

should give you access to the complete manual.

diffutils 2.8.7-cvs January 2008 DIFF(1)

Technorati Tags: DIFF, Linux Man Pages

January 4, 2009 -- SORT
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January 1, 2009 -- MODINFO
January 1, 2009 -- MKFS
January 1, 2009 -- MKNOD

DIFF3

Alex Costa — Thu, 01 Jan 2009 17:20:00 +0000

DIFF3(1) User Commands DIFF3(1)

NAME
diff3 – compare three files line by line

SYNOPSIS
diff3 [OPTION]… MYFILE OLDFILE YOURFILE

DESCRIPTION
Compare three files line by line.

-e –ed
Output unmerged changes from OLDFILE to YOURFILE into MYFILE.

-E –show-overlap
Output unmerged changes, bracketing conflicts.

-A –show-all
Output all changes, bracketing conflicts.

-x –overlap-only
Output overlapping changes.

-X Output overlapping changes, bracketing them.

-3 –easy-only
Output unmerged nonoverlapping changes.

-m –merge
Output merged file instead of ed script (default -A).

-L LABEL –label=LABEL
Use LABEL instead of file name.

-i Append `w’ and `q’ commands to ed scripts.

-a –text
Treat all files as text.

–strip-trailing-cr
Strip trailing carriage return on input.

-T –initial-tab
Make tabs line up by prepending a tab.

–diff-program=PROGRAM
Use PROGRAM to compare files.

-v –version
Output version info.

–help Output this help.

If a FILE is `-’, read standard input. Exit status is 0 if successful,
1 if conflicts, 2 if trouble.

AUTHOR
Written by Randy Smith.

REPORTING BUGS
Report bugs to <bug-gnu-utils@gnu.org>.

SEE ALSO
The full documentation for diff3 is maintained as a Texinfo manual. If
the info and diff3 programs are properly installed at your site, the
command

info diff

should give you access to the complete manual.

diffutils 2.8.7-cvs January 2008 DIFF3(1)

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DIG

Alex Costa — Thu, 01 Jan 2009 17:20:00 +0000

DIG(1) BIND9 DIG(1)

NAME
dig – DNS lookup utility

SYNOPSIS
dig [@server] [-b address] [-c class] [-f filename] [-k filename]
[-p port#] [-q name] [-t type] [-x addr] [-y [hmac:]name:key] [-4]
[-6] [name] [type] [class] [queryopt...]

dig [-h]

dig [global-queryopt...] [query...]

DESCRIPTION
dig (domain information groper) is a flexible tool for interrogating
DNS name servers. It performs DNS lookups and displays the answers that
are returned from the name server(s) that were queried. Most DNS
administrators use dig to troubleshoot DNS problems because of its
flexibility, ease of use and clarity of output. Other lookup tools tend
to have less functionality than dig.

Although dig is normally used with command-line arguments, it also has
a batch mode of operation for reading lookup requests from a file. A
brief summary of its command-line arguments and options is printed when
the -h option is given. Unlike earlier versions, the BIND 9
implementation of dig allows multiple lookups to be issued from the
command line.

Unless it is told to query a specific name server, dig will try each of
the servers listed in /etc/resolv.conf.

When no command line arguments or options are given, will perform an NS
query for “.” (the root).

It is possible to set per-user defaults for dig via ${HOME}/.digrc.
This file is read and any options in it are applied before the command
line arguments.

The IN and CH class names overlap with the IN and CH top level domains
names. Either use the -t and -c options to specify the type and class
or use the -q the specify the domain name or use “IN.” and “CH.” when
looking up these top level domains.

SIMPLE USAGE
A typical invocation of dig looks like:

dig @server name type

where:

server
is the name or IP address of the name server to query. This can be
an IPv4 address in dotted-decimal notation or an IPv6 address in
colon-delimited notation. When the supplied server argument is a
hostname, dig resolves that name before querying that name server.
If no server argument is provided, dig consults /etc/resolv.conf
and queries the name servers listed there. The reply from the name
server that responds is displayed.

name
is the name of the resource record that is to be looked up.

type
indicates what type of query is required â ANY, A, MX, SIG, etc.
type can be any valid query type. If no type argument is supplied,
dig will perform a lookup for an A record.

OPTIONS
The -b option sets the source IP address of the query to address. This
must be a valid address on one of the host’s network interfaces or
“0.0.0.0″ or “::”. An optional port may be specified by appending
“#”

The default query class (IN for internet) is overridden by the -c
option. class is any valid class, such as HS for Hesiod records or CH
for Chaosnet records.

The -f option makes dig operate in batch mode by reading a list of
lookup requests to process from the file filename. The file contains a
number of queries, one per line. Each entry in the file should be
organized in the same way they would be presented as queries to dig
using the command-line interface.

If a non-standard port number is to be queried, the -p option is used.
port# is the port number that dig will send its queries instead of the
standard DNS port number 53. This option would be used to test a name
server that has been configured to listen for queries on a non-standard
port number.

The -4 option forces dig to only use IPv4 query transport. The -6
option forces dig to only use IPv6 query transport.

The -t option sets the query type to type. It can be any valid query
type which is supported in BIND 9. The default query type is “A”,
unless the -x option is supplied to indicate a reverse lookup. A zone
transfer can be requested by specifying a type of AXFR. When an
incremental zone transfer (IXFR) is required, type is set to ixfr=N.
The incremental zone transfer will contain the changes made to the zone
since the serial number in the zone’s SOA record was N.

The -q option sets the query name to name. This useful do distinguish
the name from other arguments.

Reverse lookups â mapping addresses to names â are simplified by the -x
option. addr is an IPv4 address in dotted-decimal notation, or a
colon-delimited IPv6 address. When this option is used, there is no
need to provide the name, class and type arguments. dig automatically
performs a lookup for a name like 11.12.13.10.in-addr.arpa and sets the
query type and class to PTR and IN respectively. By default, IPv6
addresses are looked up using nibble format under the IP6.ARPA domain.
To use the older RFC1886 method using the IP6.INT domain specify the -i
option. Bit string labels (RFC2874) are now experimental and are not
attempted.

To sign the DNS queries sent by dig and their responses using
transaction signatures (TSIG), specify a TSIG key file using the -k
option. You can also specify the TSIG key itself on the command line
using the -y option; hmac is the type of the TSIG, default HMAC-MD5,
name is the name of the TSIG key and key is the actual key. The key is
a base-64 encoded string, typically generated by dnssec-keygen(8).
Caution should be taken when using the -y option on multi-user systems
as the key can be visible in the output from ps(1) or in the shell’s
history file. When using TSIG authentication with dig, the name server
that is queried needs to know the key and algorithm that is being used.
In BIND, this is done by providing appropriate key and server
statements in named.conf.

QUERY OPTIONS
dig provides a number of query options which affect the way in which
lookups are made and the results displayed. Some of these set or reset
flag bits in the query header, some determine which sections of the
answer get printed, and others determine the timeout and retry
strategies.

Each query option is identified by a keyword preceded by a plus sign
(+). Some keywords set or reset an option. These may be preceded by the
string no to negate the meaning of that keyword. Other keywords assign
values to options like the timeout interval. They have the form
+keyword=value. The query options are:

+[no]tcp
Use [do not use] TCP when querying name servers. The default
behavior is to use UDP unless an AXFR or IXFR query is requested,
in which case a TCP connection is used.

+[no]vc
Use [do not use] TCP when querying name servers. This alternate
syntax to +[no]tcp is provided for backwards compatibility. The
“vc” stands for “virtual circuit”.

+[no]ignore
Ignore truncation in UDP responses instead of retrying with TCP. By
default, TCP retries are performed.

+domain=somename
Set the search list to contain the single domain somename, as if
specified in a domain directive in /etc/resolv.conf, and enable
search list processing as if the +search option were given.

+[no]search
Use [do not use] the search list defined by the searchlist or
domain directive in resolv.conf (if any). The search list is not
used by default.

+[no]showsearch
Perform [do not perform] a search showing intermediate results.

+[no]defname
Deprecated, treated as a synonym for +[no]search

+[no]aaonly
Sets the “aa” flag in the query.

+[no]aaflag
A synonym for +[no]aaonly.

+[no]adflag
Set [do not set] the AD (authentic data) bit in the query. The AD
bit currently has a standard meaning only in responses, not in
queries, but the ability to set the bit in the query is provided
for completeness.

+[no]cdflag
Set [do not set] the CD (checking disabled) bit in the query. This
requests the server to not perform DNSSEC validation of responses.

+[no]cl
Display [do not display] the CLASS when printing the record.

+[no]ttlid
Display [do not display] the TTL when printing the record.

+[no]recurse
Toggle the setting of the RD (recursion desired) bit in the query.
This bit is set by default, which means dig normally sends
recursive queries. Recursion is automatically disabled when the
+nssearch or +trace query options are used.

+[no]nssearch
When this option is set, dig attempts to find the authoritative
name servers for the zone containing the name being looked up and
display the SOA record that each name server has for the zone.

+[no]trace
Toggle tracing of the delegation path from the root name servers
for the name being looked up. Tracing is disabled by default. When
tracing is enabled, dig makes iterative queries to resolve the name
being looked up. It will follow referrals from the root servers,
showing the answer from each server that was used to resolve the
lookup.

+[no]cmd
Toggles the printing of the initial comment in the output
identifying the version of dig and the query options that have been
applied. This comment is printed by default.

+[no]short
Provide a terse answer. The default is to print the answer in a
verbose form.

+[no]identify
Show [or do not show] the IP address and port number that supplied
the answer when the +short option is enabled. If short form answers
are requested, the default is not to show the source address and
port number of the server that provided the answer.

+[no]comments
Toggle the display of comment lines in the output. The default is
to print comments.

+[no]stats
This query option toggles the printing of statistics: when the
query was made, the size of the reply and so on. The default
behavior is to print the query statistics.

+[no]qr
Print [do not print] the query as it is sent. By default, the query
is not printed.

+[no]question
Print [do not print] the question section of a query when an answer
is returned. The default is to print the question section as a
comment.

+[no]answer
Display [do not display] the answer section of a reply. The default
is to display it.

+[no]authority
Display [do not display] the authority section of a reply. The
default is to display it.

+[no]additional
Display [do not display] the additional section of a reply. The
default is to display it.

+[no]all
Set or clear all display flags.

+time=T
Sets the timeout for a query to T seconds. The default timeout is 5
seconds. An attempt to set T to less than 1 will result in a query
timeout of 1 second being applied.

+tries=T
Sets the number of times to try UDP queries to server to T instead
of the default, 3. If T is less than or equal to zero, the number
of tries is silently rounded up to 1.

+retry=T
Sets the number of times to retry UDP queries to server to T
instead of the default, 2. Unlike +tries, this does not include the
initial query.

+ndots=D
Set the number of dots that have to appear in name to D for it to
be considered absolute. The default value is that defined using the
ndots statement in /etc/resolv.conf, or 1 if no ndots statement is
present. Names with fewer dots are interpreted as relative names
and will be searched for in the domains listed in the search or
domain directive in /etc/resolv.conf.

+bufsize=B
Set the UDP message buffer size advertised using EDNS0 to B bytes.
The maximum and minimum sizes of this buffer are 65535 and 0
respectively. Values outside this range are rounded up or down
appropriately. Values other than zero will cause a EDNS query to be
sent.

+edns=#
Specify the EDNS version to query with. Valid values are 0 to 255.
Setting the EDNS version will cause a EDNS query to be sent.
+noedns clears the remembered EDNS version.

+[no]multiline
Print records like the SOA records in a verbose multi-line format
with human-readable comments. The default is to print each record
on a single line, to facilitate machine parsing of the dig output.

+[no]fail
Do not try the next server if you receive a SERVFAIL. The default
is to not try the next server which is the reverse of normal stub
resolver behavior.

+[no]besteffort
Attempt to display the contents of messages which are malformed.
The default is to not display malformed answers.

+[no]dnssec
Requests DNSSEC records be sent by setting the DNSSEC OK bit (DO)
in the OPT record in the additional section of the query.

+[no]sigchase
Chase DNSSEC signature chains. Requires dig be compiled with
-DDIG_SIGCHASE.

+trusted-key=####
Specifies a file containing trusted keys to be used with +sigchase.
Each DNSKEY record must be on its own line.

If not specified dig will look for /etc/trusted-key.key then
trusted-key.key in the current directory.

Requires dig be compiled with -DDIG_SIGCHASE.

+[no]topdown
When chasing DNSSEC signature chains perform a top-down validation.
Requires dig be compiled with -DDIG_SIGCHASE.

+[no]nsid
Include an EDNS name server ID request when sending a query.

MULTIPLE QUERIES
The BIND 9 implementation of dig supports specifying multiple queries
on the command line (in addition to supporting the -f batch file
option). Each of those queries can be supplied with its own set of
flags, options and query options.

In this case, each query argument represent an individual query in the
command-line syntax described above. Each consists of any of the
standard options and flags, the name to be looked up, an optional query
type and class and any query options that should be applied to that
query.

A global set of query options, which should be applied to all queries,
can also be supplied. These global query options must precede the first
tuple of name, class, type, options, flags, and query options supplied
on the command line. Any global query options (except the +[no]cmd
option) can be overridden by a query-specific set of query options. For
example:

dig +qr www.isc.org any -x 127.0.0.1 isc.org ns +noqr

shows how dig could be used from the command line to make three
lookups: an ANY query for www.isc.org, a reverse lookup of 127.0.0.1
and a query for the NS records of isc.org. A global query option of +qr
is applied, so that dig shows the initial query it made for each
lookup. The final query has a local query option of +noqr which means
that dig will not print the initial query when it looks up the NS
records for isc.org.

IDN SUPPORT
If dig has been built with IDN (internationalized domain name) support,
it can accept and display non-ASCII domain names. dig appropriately
converts character encoding of domain name before sending a request to
DNS server or displaying a reply from the server. If you’d like to turn
off the IDN support for some reason, defines the IDN_DISABLE
environment variable. The IDN support is disabled if the variable is
set when dig runs.

FILES
/etc/resolv.conf

${HOME}/.digrc

SEE ALSO
host(1), named(8), dnssec-keygen(8), RFC1035.

BUGS
There are probably too many query options.

BIND9 Jun 30, 2000 DIG(1)

Technorati Tags: DIG, Linux Man Pages

January 4, 2009 -- SORT
January 1, 2009 -- MKDIRHIER
January 1, 2009 -- MODINFO
January 1, 2009 -- MKFS
January 1, 2009 -- MKNOD

CHROOT

Alex Costa — Thu, 01 Jan 2009 17:20:00 +0000

CHROOT(1) User Commands CHROOT(1)

NAME
chroot – run command or interactive shell with special root directory

SYNOPSIS
chroot NEWROOT [COMMAND...]
chroot OPTION

DESCRIPTION
Run COMMAND with root directory set to NEWROOT.

–help display this help and exit

–version
output version information and exit

If no command is given, run “${SHELL} -i” (default: /bin/sh).

AUTHOR
Written by Roland McGrath.

REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.

DIRNAME

Alex Costa — Thu, 01 Jan 2009 17:20:00 +0000

DIRNAME(1) User Commands DIRNAME(1)

NAME
dirname – strip non-directory suffix from file name

SYNOPSIS
dirname NAME
dirname OPTION

DESCRIPTION
Print NAME with its trailing /component removed; if NAME contains no
/’s, output `.’ (meaning the current directory).

–help display this help and exit

–version
output version information and exit

EXAMPLES
dirname /usr/bin/sort
Output “/usr/bin”.

dirname stdio.h
Output “.”.

AUTHOR
Written by David MacKenzie and Jim Meyering.

REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.

HOSTNAME

Alex Costa — Thu, 01 Jan 2009 17:20:00 +0000

HOSTNAME(1) Linux Programmer’s Manual HOSTNAME(1)

NAME
hostname – show or set the system’s host name
domainname – show or set the system’s NIS/YP domain name
dnsdomainname – show the system’s DNS domain name
nodename – show or set the system’s DECnet node name

SYNOPSIS
hostname [-v] [-a] [--alias] [-d] [--domain] [-f] [--fqdn] [-i] [--ip-
address] [--long] [-s] [--short] [-y] [-n] [--node]

hostname [-v] [-F filename] [--file filename] [hostname]

domainname [-v] [-F filename] [--file filename] [name]

nodename [-v] [-F filename] [--file filename] [name]

hostname [-v] [-h] [--help] [-V] [--version]

dnsdomainname [-v]

DESCRIPTION
Hostname is the program that is used to either set or display the cur-
rent host, domain or node name of the system. These names are used by
many of the networking programs to identify the machine. The domain
name is also used by NIS/YP.

GET NAME
When called without any arguments, the program displays the current
names:

hostname will print the name of the system as returned by the gethost-
name(2) function.

nodename will print the DECnet node name of the system as returned by
the getnodename(2) function.

dnsdomainname will print the domain part of the FQDN (Fully Qualified
Domain Name). The complete FQDN of the system is returned with hostname
–fqdn.

The function gethostname(2) is used to get the hostname. Only when the
hostname -s is called will gethostbyname(3) be called. The difference
in gethostname(2) and gethostbyname(3) is that gethostbyname(3) is net-
work aware, so it consults /etc/nsswitch.conf and /etc/host.conf to
decide whether to read information in /etc/sysconfig/network or
/etc/hosts the hostname is also set when the network interface is
brought up.

SET NAME
When called with one argument or with the –file option, the commands
set the host name, the NIS/YP domain name or the node name.

Note, that only the super-user can change the names.

It is not possible to set the FQDN or the DNS domain name with the dns-
domainname command (see THE FQDN below).

The host name is usually set once at system startup in
/etc/rc.d/rc.inet1 or /etc/init.d/boot (normally by reading the con-
tents of a file which contains the host name, e.g. /etc/hostname).

THE FQDN
You can’t change the FQDN (as returned by hostname –fqdn) or the DNS
domain name (as returned by dnsdomainname) with this command. The FQDN
of the system is the name that the resolver(3) returns for the host
name.

Technically: The FQDN is the name gethostbyname(2) returns for the host
name returned by gethostname(2). The DNS domain name is the part after
the first dot.

Therefore it depends on the configuration (usually in /etc/host.conf)
how you can change it. Usually (if the hosts file is parsed before DNS
or NIS) you can change it in /etc/hosts.

OPTIONS
-a, –alias
Display the alias name of the host (if used).

-d, –domain
Display the name of the DNS domain. Don’t use the command
domainname to get the DNS domain name because it will show the
NIS domain name and not the DNS domain name. Use dnsdomainname
instead.

-F, –file filename
Read the host name from the specified file. Comments (lines
starting with a `#’) are ignored.

-f, –fqdn, –long
Display the FQDN (Fully Qualified Domain Name). A FQDN consists
of a short host name and the DNS domain name. Unless you are
using bind or NIS for host lookups you can change the FQDN and
the DNS domain name (which is part of the FQDN) in the
/etc/hosts file.

-h, –help
Print a usage message and exit.

-i, –ip-address
Display the IP address(es) of the host.

-n, –node
Display the DECnet node name. If a parameter is given (or –file
name ) the root can also set a new node name.

-s, –short
Display the short host name. This is the host name cut at the
first dot.

-V, –version
Print version information on standard output and exit success-
fully.

-v, –verbose
Be verbose and tell what’s going on.

FILES
/etc/hosts

AUTHOR
Peter Tobias, <tobias@et-inf.fho-emden.de>
Bernd Eckenfels, <net-tools@lina.inka.de> (NIS and manpage).
Steve Whitehouse, <SteveW@ACM.org> (DECnet support and manpage).

net-tools 28 Jan 1996 HOSTNAME(1)

Technorati Tags: HOSTNAME, Linux Man Pages

January 1, 2009 -- HOSTNAME
January 1, 2009 -- HOSTNAME
January 4, 2009 -- SORT
January 1, 2009 -- MKDIRHIER
January 1, 2009 -- MODINFO

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