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Commands tagged bash from sorted by
Terminal - Commands tagged bash - 716 results
ln -s /BASE/* /TARGET/
2013-09-12 18:47:35
User: thehitman
Functions: ln
Tags: bash
5

Simple and easy to remember, if it already exists then it just ignores it.

rename 's/.xls/.ods/g' *.xls
<Meta-p> (aka <ALT+P>)
2013-09-10 17:13:02
User: hackerb9
Tags: history bash tcsh
9

[Click the "show sample output" link to see how to use this keystroke.]

Meta-p is one of my all time most used and most loved features of working at the command line. It's also one that surprisingly few people know about. To use it with bash (actually in any readline application), you'll need to add a couple lines to your .inputrc then have bash reread the .inputrc using the bind command:

echo '"\en": history-search-forward' >> ~/.inputrc

echo '"\ep": history-search-backward' >> ~/.inputrc

bind -f ~/.inputrc

  I first learned about this feature in tcsh. When I switched over to bash about fifteen years ago, I had assumed I'd prefer ^R to search in reverse. Intuitively ^R seemed better since you could search for an argument instead of a command. I think that, like using a microkernel for the Hurd, it sounded so obviously right fifteen years ago, but that was only because the older way had benefits we hadn't known about.

  I think many of you who use the command line as much as I do know that we can just be thinking about what results we want and our fingers will start typing the commands needed. I assume it's some sort of parallel processing going on with the linguistic part of the brain. Unfortunately, that parallelism doesn't seem to work (at least for me) with searching the history. I realize I can save myself typing using the history shortly after my fingers have already started "speaking". But, when I hit ^R in Bash, everything I've already typed gets ignored and I have to stop and think again about what I was doing. It's a small bump in the road but it can be annoying, especially for long-time command line users. Usually M-p is exactly what I need to save myself time and trouble.

  If you use the command line a lot, please give Meta-p a try. You may be surprised how it frees your brain to process more smoothly in parallel. (Or maybe it won't. Post here and let me know either way. ☺)

function garg () { tail -n 1 ${HISTFILE} | awk "{ print \$$1 }" }
2013-09-10 04:07:46
User: plasticphyte
Functions: awk tail
0

This gets the Nth argument in the last line of your history file. This is useful where history is being written after each command, and you want to use arguments from the previous command in the current command, such as when doing copies/moving directories etc.

I wrote this after getting irritated with having to continually type in long paths/arguments.

You could also use $_ if all you want is the last argument.

du -hd1 | sort -hr
sh -c 'url="http://youtu.be/MejbOFk7H6c"; vid="`for i in ".*youtu\.be/\([^\/&?#]\+\)" ".*youtu.\+v[=/]\([^\/&?#]\+\)" ".*youtu.\+embed/\([^\/&?#]\+\)"; do expr "${url}" : "${i}"; done`"; if [ -n "${vid}" ]; then echo ${vid}; else echo "${url}"; fi'
2013-09-04 19:33:09
User: qwertyroot
Functions: echo sh
2

url can be like any one of followings:

url="MejbOFk7H6c" url="http://youtu.be/MejbOFk7H6c" url="https://youtube.com/watch?feature=player_embedded&v=MejbOFk7H6c#t" url="//www.youtube.com/v/MejbOFk7H6c?hl=ru_RU&version=3&rel=0" url="http://www.youtube.com/embed/MejbOFk7H6c?feature=player_embedded"

If url mismatching, whole url will be returned.

curl ${URL} 2>/dev/null|grep "<${BLOCK}>"|sed -e "s/.*\<${BLOCK}\>\(.*\)\<\/${BLOCK}\>.*/\1/g"
2013-08-31 14:53:54
User: c3w
Functions: grep sed
0

set BLOCK to "title" or any other HTML / RSS / XML tag and curl URL to get everything in-between e.g. some text

function mkdcd () { mkdir "$1" && cd "$1" }
for i in *.flv *.mkv *.avi; do mplayer -ao null -vo null -ss 0 -endpos 1 >/dev/null "$i" 2> >(grep -qi error && echo >&2 "$i seems bad"); done
2013-08-20 22:23:11
User: sputnick
Functions: echo grep
0

If you want avoid to be annoyed when playing your favourite video files with your video player, first run this command to stash wrong files (and test tricks to play these wrong files).

diff <(sort <(md5deep -b -r /directory/1/) ) <(sort <(md5deep -b -r /directory/2/)
2013-08-19 18:20:49
Functions: diff sort
Tags: bash Linux diff
0

Compares the md5 checksums of the contents of two directories, outputting the checksum and filename where any files differ. Shows only the file name, not the full path.

nohup bash -c "while true; do ps -x | mail pascalv@mmmmail.com; sleep 3600; done" | mail pascalv@mmmmail.com &
2013-08-19 17:21:37
User: pascalv
Functions: bash mail nohup
1

Run "ps -x" (process status) in the background every hour (in this example).

The outputs of both "nohup" and "ps -x" are sent to the e-mail (instead of nohup.out and stdout and stderr).

If you like it, replace "ps -x" by the command of your choice, replace 3600 (1 hour) by the period of your choice.

You can run the command in the loop any time by killing the sleep process. For example

ps -x

2925 ? S 0:00.00 sh -c unzip E.zip >/dev/null 2>&1

11288 ? O 0:00.00 unzip E.zip

25428 ? I 0:00.00 sleep 3600

14346 pts/42- I 0:00.01 bash -c while true; do ps -x | mail pascalv; sleep 3600; done

643 pts/66 Ss 0:00.03 -bash

14124 pts/66 O+ 0:00.00 ps -x

kill 25428

You have mail in /mail/pascalv

diff <(sort <(md5deep -r /directory/1/) |cut -f1 -d' ') <(sort <(md5deep -r /directory/2/) |cut -f1 -d' ')
2013-08-18 22:13:07
Functions: cut diff sort
Tags: bash Linux diff
1

Compute the md5 checksums for the contents of two mirrored directories, then sort and diff the results. If everything matches, nothing is returned. Otherwise, any checksums which do not match, or which exist in one tree but not the other, are returned. As you might imagine, the output is useful only if no errors are found, because only the checksums, not filenames, are returned. I hope to address this, or that someone else will!

:(){ :|:& };:
ioreg -lw0 | grep IODisplayEDID | sed "/[^<]*</s///" | xxd -p -r | strings -6
function colorize() { c="--line-buffered --color=yes"; GREP_COLORS="mt=01;34" egrep $c '(^| 200 | 304 )' "${@}" | GREP_COLORS="mt=02;31" egrep $c '(^|"(GET|POST) .*[^0-9] 4[0-1][0-9] )' | GREP_COLORS="ms=02;37" egrep $c '(^|^[0-9\.]+) ';}
2013-08-14 21:05:34
User: mogsie
Functions: egrep
1

Puts a splash of color in your access logs. IP addresses are gray, 200 and 304 are green, all 4xx errors are red. Works well with e.g. "colorize access_log | less -R" if you want to see your colors while paging.

Use as inspiration for other things you might be tailing, like syslog or vmstat

Usage:

tail -f access.log | colorize
alias 2edit='xsel -b;n=pipe$RANDOM;xdotool exec --terminator -- mousepad $n -- search --sync --onlyvisible --name $n key --window %1 ctrl+v'
2013-08-11 06:18:31
User: ichbins
Functions: alias exec
1

bash output is inserted into the clipboard, then mousepad is started and the clipboard content is pasted. xsel and xdotool needs to be installed. Instead of the mousepad any other editor can be used. I've successfully tested the Sublime Text Editor and it opens a new tab for each new paste. Check Sample output for a usage example. This command is originated from here - http://goo.gl/0q9UT4

if [[ ":$PATH:" != *":$dir:"* ]]; then PATH=${PATH}:$dir; fi
2013-08-11 01:19:13
User: dmmst19
Tags: bash PATH $PATH
9

Sometimes in a script you want to make sure that a directory is in the path, and add it in if it's not already there. In this example, $dir contains the new directory you want to add to the path if it's not already present.

There are multiple ways to do this, but this one is a nice clean shell-internal approach. I based it on http://stackoverflow.com/a/1397020.

You can also do it using tr to separate the path into lines and grep -x to look for exact matches, like this:

if ! $(echo "$PATH" | tr ":" "\n" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi

which I got from http://stackoverflow.com/a/5048977.

Or replace the "echo | tr" part with a shell parameter expansion, like

if ! $(echo "${PATH//:/$'\n'}" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi

which I got from http://www.commandlinefu.com/commands/view/3209/.

There are also other more regex-y ways to do it, but I find the ones listed here easiest to follow.

Note some of this is specific to the bash shell.

open() { explorer /e, $(cygpath -wap "${1:-$PWD}"); }
2013-08-08 14:49:15
User: applemcg
0

use the shell default positional parameter syntax ${X:-default} in lieu of testing.

$ ps -LF -u user
2013-08-06 21:50:48
User: jld
Functions: ps
Tags: bash processes
0

Piping ps into grep is mostly useless: ps has its own filter options like -u and -C

for i in '/tmp/file 1.txt' '/tmp/file 2.jpg'; do ln -s "$i" "$i LINK"; done
2013-08-02 08:30:50
User: qwertyroot
Functions: ln
0

Replace

'/tmp/file 1.txt' '/tmp/file 2.jpg'

with

"$NAUTILUS_SCRIPT_SELECTED_FILE_PATHS"

for Nautilus script

Or with

%F

for Thunar action

If you linking the symlinks itself, but want to link to source files instead of symlinks, use

"`readlink -m "$i"`"

instead of

"$i"

like this:

for i in '/tmp/file 1.txt' '/tmp/file 2.jpg'; do ln -s "`readlink -m "$i"`" "$i LINK"; done

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

for fil in *.JPG; do datepath="$(identify -verbose $fil | grep DateTimeOri | awk '{print $2"_"$3 }' | sed s%:%_%g)"; mv -v $fil $datepath.jpg; done
2013-08-02 01:42:04
Functions: mv
0

Requires ImageMagick.

Extracts date taken from image and renames it properly.

Based on StackOverflow answer.

rhost() { if [[ $1 =~ ^[0-9]+$ ]]; then sed -i "$1"d ${HOME}/.ssh/known_hosts; else echo "rhost [n]"; fi }
2013-08-01 21:10:34
User: lowjax
Functions: echo sed
-1

Quickly remove the conflicting line (key) from current users known_hosts file when there is an SSH host conflict. Very nice when you get tired of writing out full commands. Ideally you would place this into your .bash_profile

Usage: rhost [n]

Example: rhost 33 (removes line 33 from ~/.ssh/known_hosts)

Function assumes the $HOME exists, you could alternatively use "~/.ssh/known_hosts"

Mac OSX likes a space for sed -i "$1" d

open(){ if [[ -n "$1" ]];then explorer /e, $(cygpath -mal "$PWD/$1");else explorer /e, $(cygpath -mal "$PWD");fi }
2013-07-31 01:15:14
User: lowjax
1

This alternative either opens the current working directory by just issuing the open function in the commandline. Or you can specify what directory you would like to open.

Example: open /cygdrive/c/Windows

Usage: open [path]

When no option is specified it will open the current working directory

for m in `df -P | awk -F ' ' '{print $NF}' | sed -e "1d"`;do n=`df -P | grep "$m$" | awk -F ' ' '{print $5}' | cut -d% -f1`;i=0;if [[ $n =~ ^-?[0-9]+$ ]];then printf '%-25s' $m;while [ $i -lt $n ];do echo -n '=';let "i=$i+1";done;echo " $n";fi;done
2013-07-29 20:12:39
User: drockney
Functions: awk cut echo grep printf sed
Tags: bash
5

Automatically drops mount points that have non-numeric sizes (e.g. /proc). Tested in bash on Linux and AIX.

echo -e "\e[3$(( $RANDOM * 6 / 32767 + 1 ))mHello World!"
2013-07-28 13:01:12
User: nst
Functions: echo
Tags: bash color random
0

The expression $(( $RANDOM * 6 / 32767 + 1 )) generates a random number between 1 and 6, which is then inserted into the escape sequence \e[3_m to switch the foreground color of the terminal to either red, green, yellow, blue, purple or cyan.

The color can be reset using the escape sequence \e[0m.

The full list of colors can be found here: https://wiki.archlinux.org/index.php/Color_Bash_Prompt#List_of_colors_for_prompt_and_Bash