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Commands tagged Linux from sorted by
Terminal - Commands tagged Linux - 230 results
ips(){ for if in ${1:-$(ip link list|grep '^.: '|cut -d\ -f2|cut -d: -f1)};do cur=$(ifconfig $if|grep "inet addr"|sed 's/.*inet addr:\([0-9\.]*\).*/\1/g');printf '%-5s%-15s%-15s\n' $if $cur $(nc -s $cur sine.cluenet.org 128 2>/dev/null||echo $cur);done;}
2009-08-07 10:04:46
User: frozenfire
Functions: cut echo grep ifconfig link sed
-3

Gets the internal and external IP addresses of all your interfaces, or the ones given as arguments

ulimit -s 64
2009-08-06 10:40:25
User: ioggstream
Functions: ulimit
Tags: Linux ulimit
1

default stack size is 10M. This makes your multithread app filling rapidly your memory.

on my PC I was able to create only 300thread with default stack size.

Lower the default stack size to the one effectively used by your threads, let you create more.

ex. putting 64k I was able to create more than 10.000threads.

Obviously ...your thread shouldn't need more than 64k ram!!!

grep -r . /sys/class/net/eth0/statistics
2009-08-05 08:20:39
User: olorin
Functions: grep
Tags: Linux
4

Within /proc and /sys there are a lot of subdirectories, which carry pseudofiles with only one value as content. Instead of cat-ing all single files (which takes quite a time) or do a "cat *" (which makes it hard to find the filename/content relation), just grep recursively for . or use "grep . /blabla/*" (star instead of -r flag).

For better readability you might also want to pipe the output to "column -t -s : ".

/sbin/kexec -l /boot/$KERNEL --append="$KERNELPARAMTERS" --initrd=/boot/$INITRD; sync; /sbin/kexec -e
2009-08-03 07:36:49
User: olorin
Tags: Linux boot kexec
21

If you are doing some tests which require reboots (e. g. startup skripts, kernel module parameters, ...), this is very time intensive, if you have got a hardware with a long pre-boot phase due to hardware checks.

At this time, kexec can help, which only restarts the kernel with all related stuff.

First the kernel to be started is loaded, then kexec -e jumps up to start it.

Is as hard as a reboot -f, but several times faster (e. g. 1 Minute instead of 12 on some servers here).

ifconfig | awk '/ddr:[0-9]/ {sub(/addr:/, ""); print $2}'
2009-07-31 09:30:54
User: danny_b85
Functions: awk ifconfig
Tags: Linux ifconfig
1

The initial version of this command also outputted extra empty lines, so it went like this:

192.168.166.48

127.0.0.1

This happened on Ubuntu, i haven't tested on anything else.

ipconfig getpacket en0 | grep yi| sed s."yiaddr = "."en0: ". ipconfig getpacket en1 | grep yi| sed s."yiaddr = "."en1: ".
ifconfig | awk -F':| +' '/ddr:/{print $4}'
2009-07-25 22:51:08
User: 0x89
Functions: awk ifconfig
Tags: Linux ifconfig
1

and, a lot uglier, with sed:

ifconfig | sed -n '/inet addr:/s/[^:]\+:\(\S\+\).*/\1/p'

Edit:

Wanted to be shorter than the perl version. Still think that the perl version is the best..

ifconfig | grep "inet [[:alpha:]]\+" | cut -d: -f2 | cut -d' ' -f2
2009-07-24 13:16:37
User: feraf
Functions: cut grep ifconfig
Tags: Linux ifconfig
-6

Get the IP address of all your network cards.

ifconfig | grep "inet addr" | cut -d: -f2 | cut -d' ' -f1
ifconfig | perl -nle'/dr:(\S+)/ && print $1'
2009-07-23 09:33:31
User: xsawyerx
Functions: ifconfig perl
11

Fetches the IPs and ONLY the IPs from ifconfig. Simplest, shortest, cleanest.

Perl is too good to be true...

(P.S.: credit should go to Peteris Krumins at catonmat.net)

lomount -diskimage /path/to/your/backup.img -partition 1 /mnt/foo
4

Instead of calculating the offset and providing an offset option to mount, let lomount do the job for you by just providing the partition number you would like to loop mount.

/originalInstall/gem list | tr -d '(),' | xargs -L 1 sudo ./gemInst.sh
2009-07-09 21:46:06
User: snakerdlk
Functions: sudo tr xargs
Tags: bash Linux
0

gemInst.sh:

#!/bin/bash

for i in $@; do

if [ "$1" != "$i" ]

then

echo /newInstall/gem install $1 -v=\"$i\"

/newInstall/gem install $1 -v="$i"

if [ "$?" != "0" ]

then

echo -e "\n\nGEM INSTALL ERROR: $1\n\n"

echo "$1" > gemInst.err

fi

fi

done

watch -t -n1 "date +%T|figlet"
2009-06-21 01:02:37
User: dennisw
Functions: watch
43

This command displays a clock on your terminal which updates the time every second. Press Ctrl-C to exit.

A couple of variants:

A little bit bigger text:

watch -t -n1 "date +%T|figlet -f big"

You can try other figlet fonts, too.

Big sideways characters:

watch -n 1 -t '/usr/games/banner -w 30 $(date +%M:%S)'

This requires a particular version of banner and a 40-line terminal or you can adjust the width ("30" here).

dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d'
2009-06-19 10:23:38
User: plasticdoc
Functions: sed
Tags: Linux sed dpkg
4

will show:

installed linux headers, image, or modules: /^ii/!d

avoiding current kernel: /'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d

only application names: s/^[^ ]* [^ ]* \([^ ]*\).*/\1/

avoiding stuff without a version number: /[0-9]/!d

dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d' | xargs sudo apt-get -y purge
2009-06-19 10:11:00
User: plasticdoc
Functions: sed sudo xargs
6

will purge:

only installed apps: /^ii/!d

avoiding current kernel stuff: /'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d

using app names: s/^[^ ]* [^ ]* \([^ ]*\).*/\1/

avoiding stuff without a version number: /[0-9]/!d

grep -2 -iIr "err\|warn\|fail\|crit" /var/log/*
2009-06-17 19:41:04
User: miketheman
Functions: grep
6

Using the grep command, retrieve all lines from any log files in /var/log/ that have one of the problem states

date -d '1 day ago'; date -d '11 hour ago'; date -d '2 hour ago - 3 minute'; date -d '16 hour'
2009-06-01 10:41:56
User: LrdShaper
Functions: date
5

With this command you can get a previous or future date or time. Where can you use this? How about finding all files modified or created in the last 5 mins?

touch -t `echo $(date -d "5 minute ago" "+%G%m%d%H%M.%S")` me && find . -type f -newer me

List all directories created since last week?

touch -t `echo $(date -d "1 week ago" "+%G%m%d%H%M.%S")` me && find . -type d -cnewer me

I'm sure you can think of more ways to use it. Requires coreutils package.

net rpc shutdown -I ipAddressOfWindowsPC -U username%password
2009-05-31 07:18:01
User: LrdShaper
Functions: shutdown
Tags: Linux windows
105

This will issue a shutdown command to the Windows machine. username must be an administrator on the Windows machine. Requires samba-common package installed. Other relevant commands are:

net rpc shutdown -r : reboot the Windows machine

net rpc abortshutdown : abort shutdown of the Windows machine

Type:

net rpc

to show all relevant commands

for i in `svn status | egrep '^(M|A)' | sed -r 's/\+\s+//' | awk '{ print $2 }'` ; do if [ ! -d $i ] ; then php -l $i ; fi ; done
2009-05-29 23:59:28
Functions: awk egrep sed
Tags: svn Linux PHP
0

Really only valuable in a PHP-only project directory. This is using standard linux versions of the tools. On most older BSD variants of sed, use -E instead of -r. Or use: sed 's/\+[[:space:]]\{1,\}//' instead.

lsof -nP +p 24073 | grep -i listen | awk '{print $1,$2,$7,$8,$9}'
lsb_release -d
pwsafe -qa "gpg keys"."$(finger `whoami` | grep Name | awk '{ print $4" "$5 }')"
2009-05-07 14:49:56
User: denzuko
0

From time to time one forgets either thier gpg key or other passphrases. This can be very problematic in most cases. But luckily there's this script. Its based off of pwsafe which is a unix commandline program that manages encrypted password databases. For more info on pwsafe visit, http://nsd.dyndns.org/pwsafe/.

What this script does is it will help you store all your passphrases for later on and allow you to copy it to your clipboard so you can just paste it in, all with one password. Pretty neat no?

You can find future releases of this and many more scripts at The Teachings of Master Denzuko - denzuko.wordpress.com.

alias somafm='read -p "Which station? "; mplayer --reallyquiet -vo none -ao sdl http://somafm.com/startstream=${REPLY}.pls'
2009-05-05 12:13:46
User: denzuko
Functions: alias
-2

This is the alias command that I discussed in my prior release which you can add to your ~/.bashrc.

This command asks for the station name and then connects to somafm, Great for those who have linux home entertainment boxes and ssh enabled on them, just for the CLI fiends out there ( I know I'm one of them ;)

You can find future releases of this and many more scripts at the teachings of master denzuko - denzuko.co.cc.

lynx -dump randomfunfacts.com | grep -A 3 U | sed 1D
2009-05-05 07:52:10
User: xizdaqrian
Functions: grep sed
0

This is a working version, though probably clumsy, of the script submitted by felix001. This works on ubuntu and CygWin. This would be great as a bash function, defined in .bashrc. Additionally it would work as a script put in the path.

read -p "Which station? "; mplayer --reallyquiet -vo none -ao sdl http://somafm.com/startstream=${REPLY}.pls
2009-05-04 00:26:19
User: denzuko
Functions: read
11

This command asks for the station name and then connects to somafm, Great for those who have linux home entertainment boxes and ssh enabled on them, just for the CLI fiends out there ( I know I'm one of them ;)

Also, don't forget to add this as alias(ie alias somafm="read -p 'Which Station? "; mplayer --reallyquite -vo none -ao sdl