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Commands tagged Linux from sorted by
Terminal - Commands tagged Linux - 216 results
sudo dpkg -i `ls -tr *.deb | tail -n4`
2011-10-09 14:20:11
User: _john
Functions: sudo tail
Tags: Debian Linux kernel dpkg
0
Up
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Install 4 new package files

after kernel build with make deb-pkg, I like to install the 4 newest packages that exist in the directory. Beware: might be fewer for you....

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apt-get remove $(dpkg -l | awk "/^ii linux-(image|headers)/ && ! /`uname -r`/ {print \$2}")
2011-10-09 13:58:47
User: _john
Functions: apt awk
Tags: Debian Linux awk grep kernel dpkg aptitude
0
Up
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Remove all unused kernels with apt-get

since awk was already there one can use it instead of the 2 greps. might not be faster, but fast enough

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sed 's/.$//' Win-file.txt
2011-09-15 19:07:51
User: totti
Functions: sed
Tags: Linux windows text conversion
-1
Up
Down
Convert windows text file to linux text document
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tr -d "\r" < dos.txt > linux.txt
2011-09-09 18:53:34
User: totti
Functions: tr
Tags: Linux windows text conversion
0
Up
Down
Convert windows text file to linux text document
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while true ; do nc -l 80 < index.html ; done
2011-08-31 15:17:33
User: ztank1013
Functions: true
Tags: bash Linux netcat nc web server
10
Up
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One command line web server on port 80 using nc (netcat)

Very simple web server listening on port 80 will serve index.html file or whatever file you like pointing your browser at http://your-IP-address/index.html for example.

If your web server is down for maintenance and you'd like to inform your visitors about it, quickly and easily, you just have to put into the index.html file the right HTML code and you are done! Of course you need to be root to run the command using port 80.

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find /var/spool/mqueue -type f -mtime +7 | perl -lne unlink
2011-08-19 15:22:02
User: mengesb
Functions: find perl
Tags: bash Linux perl find
0
Up
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Find all e-mails older than 7 days in the queue and delete them

Find all files in /var/spool/mqueue older than 7 days, pass to perl to efficiently delete them (faster than xargs or -exec when you've got millions or hundreds of thousands to delete). Naturally the type, directory, and file age vars can be adjusted to meet your specific needs.

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ln -nsf <TARGET> <LINK>
2011-07-14 14:07:06
User: rdc
Functions: ln
Tags: Linux symlinks
21
Up
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Repoint an existing symlink to a new location

Instead of deleting an existing symlink and then re-creating it pointing at the new location, it is possible to perform the same action with this one command.

Interesting discussion on whether this is possible to do atomically here: http://answers.google.com/answers/threadview?id=526119

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find /myfs -size +209715200c -exec du -m {} \; |sort -nr |head -10
2011-07-07 21:12:46
User: arlequin
Functions: du find head sort
Tags: Linux size find unix ksh aix korn shell
2
Up
Down
List top 10 files in filesystem or mount point bigger than 200MB

Specify the size in bytes using the 'c' option for the -size flag. The + sign reads as "bigger than". Then execute du on the list; sort in reverse mode and show the first 10 occurrences.

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ykpersonalize -1 -ostatic-ticket -ostrong-pw1 -ostrong-pw2
2011-05-13 04:00:52
User: switchrodeo720
Tags: Linux yubikey yubico strong password
-1
Up
Down
Static Yubikey 2.2 Password Using Programming Slot 1

By default, slot 1 is used for OTP purposes and validates against the Yubikey servers. Running the command above will replace that. If you have a Yubikey 2 or above, you can change -1 to -2 and program the second slot with a strong static key.

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ip addr show eth0 | grep ether | awk '{print $2}'
2011-05-01 19:54:46
User: ryanc
Functions: awk grep
Tags: Network Linux
-2
Up
Down
List your MACs address

Linux specific, requires iproute2 (but most distros have that by default now)

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chage -d 0 -m 0 -M 60 [user]
2011-04-28 02:19:59
User: mack
Functions: chage
Tags: Linux password user expiration
0
Up
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How to expire the password to force her change [Linux]

This command is Linux compatible.

It will prompt the user for a new password at next logon

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sudo aptitude remove -P $(dpkg -l|awk '/^ii linux-image-2/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic\nlinux-image-%s-generic\n",$0,$0,$0)}')
2011-04-25 05:19:57
User: Bonster
Functions: awk sed sudo
Tags: Debian Linux awk grep kernel dpkg aptitude
-1
Up
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Remove all unused kernels with apt-get

Same as 7272 but that one was too dangerous

so i added -P to prompt users to continue or cancel

Note the double space: "...^ii␣␣linux-image-2..."

Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel).

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fig2dev -L eps file.fig file.eps
2011-04-25 01:02:25
User: droidery29
Tags: Linux
0
Up
Down
Converting your Xfig 'fig' files to 'eps' and others

There is a huge number of supported "languages" to which you can export your .fig figures to. See. 'man fig2dev' (http://linux.die.net/man/1/fig2dev).

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php -r 'function a(){$i=10;while($i--)echo str_repeat(" ",rand(1,79))."*".PHP_EOL;}$i=99;while($i--){a();echo str_repeat(" ",34)."Happy New Year 2011".PHP_EOL;a();usleep(200000);}'
2011-04-21 05:08:56
User: galymzhan
Functions: echo
Tags: Linux PHP
1
Up
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Congratulations on new year

Requires installed command line PHP. Also, try at different dimensions of terminal window

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function rot13 { if [ -r $1 ]; then cat $1 | tr '[N-ZA-Mn-za-m5-90-4]' '[A-Za-z0-9]'; else echo $* | tr '[N-ZA-Mn-za-m5-90-4]' '[A-Za-z0-9]'; fi }
2011-03-18 09:59:41
User: twjolson
Functions: cat echo tr
Tags: Linux unix tr
-5
Up
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ROT13 using the tr command

Will rot 13 whatever parameter follows 'rot13', whether it is a string or a file. Additionally, it will rot 5 each digit in a number

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alias rot13="tr a-zA-Z n-za-mN-ZA-M"
2011-03-17 11:21:19
User: mathias
Functions: alias
Tags: Linux unix tr
7
Up
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ROT13 using the tr command
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aptitude remove $(dpkg -l|awk '/^ii linux-image-2/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic\nlinux-image-%s-generic\n",$0,$0,$0)}')
2010-12-11 11:38:15
User: __
Functions: awk sed
Tags: Debian Linux awk grep kernel dpkg aptitude
7
Up
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Remove all unused kernels with apt-get

Note the double space: "...^ii␣␣linux-image-2..."

Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel).

I'm bummed that this took 228 characters. I'd like to see a simpler version.

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tar -zxvf file.tar.gz -C /tmp
2010-11-17 14:26:14
User: rdc
Functions: tar
Tags: Linux tar unzip
1
Up
Down
Unzip and untar a *.tar.gz file in one go to a specific directory

A *.tar.gz file needs to be unzipped & then untarred. Previously I might have unzipped first with

gunzip -d file.tar.gz

and then untarred the result with

tar -xvf file.tar

(Options are extract, verbose, file)

Using the -z (decompress) option on tar avoids the use of gzip (or gunzip) first.

Additionally the -C option will specify the directory to extract to.

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for I in `/sbin/lspci |awk '/VGA/{print $1}'`;do /sbin/lspci -v -s $I;done
2010-10-26 19:02:26
User: houghi
Functions: awk
Tags: Linux hardware
4
Up
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Get information on your graphics card on linux (such as graphics memory size)

Loop is needed if you have more then one card.

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lspci -v -s `lspci | awk '/VGA/{print $1}'`
2010-10-26 17:45:14
User: infinull
Functions: awk lspci
Tags: Linux hardware
1
Up
Down
Get information on your graphics card on linux (such as graphics memory size)

probably only works if you have one graphics card.

used this: http://www.cyberciti.biz/faq/howto-find-linux-vga-video-card-ram/

as reference

can be expanded, for example:

lspci -v -s `lspci | awk '/VGA/{print $1}'` | sed -n '/Memory.*, prefetchable/s/.*\[size=\([^]]\+\)\]/\1/p'

will just get the amount of prefetchable memory

compare to:

lshw -C display

which does not give the size (it does give byte ranges and you could calculate the size from that, but that's a pain)

Also uses a command which is not standard on linux; wheras lspci is a core utility provided by most systems

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inotifywait -mrq -e CREATE --format %w%f /path/to/dir | while read FILE; do chmod g=u "$FILE"; done
2010-10-21 23:36:02
User: dooblem
Functions: chmod read
Tags: Linux chmod inotify inotifywait umask
6
Up
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Trigger a command each time a file is created in a directory (inotify)

Listens for events in the directory. Each created file is displayed on stdout. Then each fileline is read by the loop and a command is run.

This can be used to force permissions in a directory, as an alternative for umask.

More details:

http://en.positon.org/post/A-solution-to-the-umask-problem%3A-inotify-to-force-permissions

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Check the Description below.
2010-10-07 04:22:32
User: hunterm
Tags: bash Linux wget curl awesome counter epic one liner
-1
Up
Down
Add together the count of users from the international Linux Counter and the dudalibre.com counter.

The command was too long for the command box, so here it is:

echo $(( `wget -qO - http://i18n.counter.li.org/ | grep 'users registered' | sed 's/.*\<font size=7\>//g' | tr '\>' ' ' | sed 's/<br.*//g' | tr ' ' '\0'` + `curl --silent http://www.dudalibre.com/gnulinuxcounter?lang=en | grep users | head -2 | tail -1 | sed 's/.*<strong>//g' | sed 's/<\/strong>.*//g'` ))

This took me about an hour to do. It uses wget and curl because, dudalibre.com blocks wget, and wget worked nicely for me.

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wget -qO - http://i18n.counter.li.org/ | grep 'users registered' | sed 's/.*\<font size=7\>//g' | tr '\>' ' ' | sed 's/<br.*//g' | tr ' ' '\0'
2010-10-07 03:19:17
User: hunterm
Functions: grep sed tr wget
Tags: Linux sed wget tr counter
-1
Up
Down
Get the amount of currently registered users from i18n.counter.li.org.
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sudo hwinfo --framebuffer
2010-10-03 14:45:02
User: hute37
Functions: sudo
Tags: Linux grub boot hwinfo
4
Up
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show framebuffer console modes to use in grub vga option

look at /boot/grub/menu.lst for somethig like:

## additional options to use with the default boot option, but not with the

## alternatives

## e.g. defoptions=vga=791 resume=/dev/hda5

## defoptions=vga=795

# defoptions=vga=873

## altoption boot targets option

## multiple altoptions lines are allowed

## e.g. altoptions=(extra menu suffix) extra boot options

## altoptions=(recovery) single

# altoptions=(verbose mode) vga=775 debug

# altoptions=(console mode) vga=ask

# altoptions=(graphic mode) quiet splash

# altoptions=(recovery mode) single

vga=(decimal value) is framebuffer mode

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wget -O - 'https://USERNAMEHERE:PASSWORDHERE@mail.google.com/mail/feed/atom' --no-check-certificate
2010-09-26 14:47:13
User: PLA
Functions: wget
Tags: Linux wget xml gmail atom
-3
Up
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Using wget to receive an XML atom feed of your Gmail inbox

I use this command in my Conky script to display the number of messages in my Gmail inbox and to list the from: and subject: fields.

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