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Commands tagged bash from sorted by
Terminal - Commands tagged bash - 712 results
old='apt-get'; new="su-${old}"; command="sudo ${old}"; alias "${new}=${command}"; $( complete | sed -n "s/${old}$/${new}/p" ); alias ${new}; complete -p ${new}
2009-08-10 00:15:05
User: Josay
Functions: alias sed
4

In Bash, when defining an alias, one usually loses the completion related to the function used in that alias (that completion is usually defined in /etc/bash_completion using the complete builtin).

It's easy to reuse the work done for that completion in order to have smart completion for our alias.

That's what is done by this command line (that's only an example but it may be very easy to reuse).

Note 1 : You can use given command line in a loop "for old in apt-get apt-cache" if you want to define aliases like that for many commands.

Note 2 : You can put the output of the command directly in your .bashrc file (after the ". /etc/bash_completion") to always have the alias and its completion

cd `dirname $_`
cd !$:h
2009-08-07 00:37:08
User: lingo
Functions: cd
25

Uses the last argument of the last executed command, and gets the directory name from it.

Use $!:t for the filename alone, without the dirname.

wget `lynx -dump http://www.ebow.com/ebowtube.php | grep .flv$ | sed 's/[[:blank:]]\+[[:digit:]]\+\. //g'`
2009-08-02 14:09:53
User: spaceyjase
Functions: grep sed wget
3

I wanted all the 'hidden' .flv files from the http link in the command line; wget seemed appropriate, fed with output from lynx, grep the flv files and the normalised via sed (to remove the numeric bullet). Similar to the 'Grab mp3 files' fu. Replace link with your own, grep arg with something more interesting ;) See here for something along the same lines...

http://www.commandlinefu.com/commands/view/1006/grab-mp3-files-from-your-favorite-netcasts-mp3blog-or-sites-that-often-have-good-mp3s

Hope you find it useful! Improvements welcome, naturally.

no_of_files=10; counter=1; while [[ $counter -le $no_of_files ]]; do echo Creating file no $counter; dd bs=1024 count=$RANDOM skip=$RANDOM if=/dev/sda of=random-file.$counter; let "counter += 1"; done
2009-07-31 16:34:47
User: rajaseelan
Functions: dd echo file
Tags: bash dd
0

Create a bunch of random files with random binary content. Basically dd dumps randomly from your hard disk to files random-file*.

[[ "$WINDOW" ]] && PS1="\u@\h:\w[$WINDOW]\$ "
2009-07-23 06:46:19
User: recursiverse
Tags: bash screen shell
4

Add this to your $HOME/.bashrc file. It will only set this prompt if it is running inside screen ($WINDOW var is set)

Looks like this...

ion@atomos:~[2]$
lynx -dump http://www.ip-adress.com/ip_tracer/?QRY=$1|sed -nr s/'^.*My IP address city: (.+)$/\1/p'
ls -drt /var/log/* | tail -n5 | xargs sudo tail -n0 -f
2009-07-22 14:44:41
User: kanaka
Functions: ls sudo tail xargs
Tags: bash tail log watch
5

This command finds the 5 (-n5) most frequently updated logs in /var/log, and then does a multifile tail follow of those log files.

Alternately, you can do this to follow a specific list of log files:

sudo tail -n0 -f /var/log/{messages,secure,cron,cups/error_log}

tar -pczf archive_name.tar.gz /path/to/dir/or/file
2009-07-17 19:53:02
User: ryuslash
Functions: tar
Tags: bash tar gzip
-2

Create a single tar.gz archive

I know it's a very basic one, but it's one I keep forgetting.

sudo rmmod pcspkr
2009-07-17 18:21:19
User: zombiedeity
Functions: rmmod sudo
8

To ensure that it will never come back, you can edit /etc/modprobe.d/blacklist

Add "blacklist pcspkr" sans quotes

infile=$1 for i in $(cat $infile) do echo $i | tr "," "\n" | sort -n | tr "\n" "," | sed "s/,$//" echo done
2009-07-12 21:23:37
User: iframe
Functions: cat echo sed sort tr
Tags: cat bash sort sed tr
0

Save the script as: sort_file

Usage: sort_file < sort_me.csv > out_file.csv

This script was originally posted by Admiral Beotch in LinuxQuestions.org on the Linux-Software forum.

I modified this script to make it more portable.

iconv -f437 -tutf8 asciiart.nfo
2009-07-11 23:50:05
User: speaker
Functions: iconv
8

Files containing ascii art (e.g. with .nfo extension) are typically not correctly reproduced at the command line when using cat. With iconv one can easily write a wrapper to solve this:

#!/bin/bash

if [ -z "$@" ]; then echo "Usage: $(basename $0) file [file] ..."

else iconv -f437 -tutf8 "$@"; fi

exit 0
for y in $(seq 2009 2011); do cal $y; done
2009-07-10 10:07:46
Functions: cal seq
Tags: bash seq cal
3

print multiple increasing years using cal - calendar -. You can also try

seq Start Increment End
/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

export IFS=$(echo -e "\n")
2009-07-09 15:25:37
User: darkpand
Functions: echo export
8

When you use a "for" construct, it cycles on every word. If you want to cycle on a line-by-line basis (and, well, you can't use xargs -n1 :D), you can set the IFS variable to .

l=500; x=500; y=200; d=-15;for i in `seq $x $d $y`; do beep -l $l -f $i;done
2009-07-07 22:12:20
Tags: bash beep sound
0

Generates a frequency sweep from $x to $y, with $d numbers inbetween each step, and with each tone lasting $l milliseconds.

? () { echo "$*" | bc -l; }
2009-06-28 20:15:30
User: fizz
Functions: bc echo
56

defines a handy function for quick calculations from cli.

once defined:

? 10*2+3
for i in *;do mv "$i" "$(echo $i | sed s/PROBLEM/FIX/g)";done
2009-06-28 01:50:25
User: AlecSchueler
Functions: mv
3

Useful if non-ascii characters in filenames have been improperly encoded. Replace "PROBLEM" with the incorrect characters (e.g. 'é'), and "FIX" with the correct ones (e.g. '?').

echo {0..1}{0..1}{0..1}{0..1}
2009-06-23 17:30:20
User: dennisw
Functions: echo
17

If you should happen to find yourself needing some binary numbers, this is a quickie way of doing it. If you need more digits, just add more "{0..1}" sequences for each digit you need. You can assign them to an array, too, and access them by their decimal equivalent for a quickie binary to decimal conversion (for larger values it's probably better to use another method). Note: this works in bash, ksh and zsh. For zsh, though, you'll need to issue a setopt KSH_ARRAYS to make the array zero-based.

binary=({0..1}{0..1}{0..1}{0..1})

echo ${binary[9]}
(Command too long..See sample Output..)
2009-06-14 20:34:37
User: mohan43u
Tags: bash sed echo tr od
-3

curl doesn't provide url-encoding for 'GET' data, it have an option '--data-urlencode', but its only for 'POST' data. Thats why I need to write down this commandline. With 'perl', 'php' and 'python', this is one liner, but just I wrote it for fun. Works in Ubuntu, will work in all linux varients(I hope it will work in unix varients also).

a=`printf "%*s" 16`;b=${a//?/{0..1\}}; echo `eval "echo $b"`
chronic () { t=$1; shift; while true; do $@; sleep $t; done & }
2009-06-13 05:57:54
User: rhythmx
Functions: sleep
3

Chronic Bash function:

chronic 3600 time # Print the time in your shell every hour chronic 60 updatedb > /dev/null # update slocate every minute

Note: use 'jobs' to list background tasks and fg/bg to take control of them.

FILENAME=${FILE##*/};FILEPATH=${FILE%/*};NOEXT=${FILENAME%\.*};EXT=${FILE##*.}
URL=http://svn.example.org/project; diff -u <(TZ=UTC svn -q log -r1:HEAD $URL | grep \|) <(TZ=UTC svn log -q $URL | grep \| | sort -k3 -t \|)
2009-06-03 14:26:55
User: sunny256
Functions: diff grep sort
Tags: bash svn
2

Lists revisions in a Subversion repository with a timestamp that doesn't follow the revision numbering order. If everything is OK, nothing is displayed.

for k in `git branch|perl -pe s/^..//`;do echo -e `git show --pretty=format:"%Cgreen%ci %Cblue%cr%Creset" $k|head -n 1`\\t$k;done|sort -r
2009-06-03 08:25:00
User: brunost
Functions: echo head perl sort
14

Print out list of all branches with last commit date to the branch, including relative time since commit and color coding.