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Commands tagged bash from sorted by
Terminal - Commands tagged bash - 695 results
alias dateh='date --help|sed -n "/^ *%%/,/^ *%Z/p"|while read l;do F=${l/% */}; date +%$F:"|'"'"'${F//%n/ }'"'"'|${l#* }";done|sed "s/\ *|\ */|/g" |column -s "|" -t'
21

If you have used bash for any scripting, you've used the date command alot. It's perfect for using as a way to create filename's dynamically within aliases,functions, and commands like below.. This is actually an update to my first alias, since a few commenters (below) had good observations on what was wrong with my first command.

# creating a date-based ssh-key for askapache.github.com

ssh-keygen -f ~/.ssh/`date +git-$USER@$HOSTNAME-%m-%d-%g` -C 'webmaster@askapache.com' # /home/gpl/.ssh/git-gplnet@askapache.github.com-04-22-10

# create a tar+gzip backup of the current directory

tar -czf $(date +$HOME/.backups/%m-%d-%g-%R-`sed -u 's/\//#/g' <<< $PWD`.tgz) . # tar -czf /home/gpl/.backups/04-22-10-01:13-#home#gpl#.rr#src.tgz .

I personally find myself having to reference

date --help

quite a bit as a result. So this nice alias saves me a lot of time. This is one bdash mofo. Works in sh and bash (posix), but will likely need to be changed for other shells due to the parameter substitution going on.. Just extend the sed command, I prefer sed to pretty much everything anyways.. but it's always preferable to put in the extra effort to go for as much builtin use as you can. Otherwise it's not a top one-liner, it's a lazyboy recliner.

Here's the old version:

alias dateh='date --help|sed "/^ *%%/,/^ *%Z/!d;s/ \+/ /g"|while read l;do date "+ %${l/% */}_${l/% */}_${l#* }";done|column -s_ -t'

This trick from my [ http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html bash_profile ]

shmore(){ local l L M="`echo;tput setab 4&&tput setaf 7` --- SHMore --- `tput sgr0`";L=2;while read l;do echo "${l}";((L++));[[ "$L" == "${LINES:-80}" ]]&&{ L=2;read -p"$M" -u1;echo;};done;}
2010-04-21 00:40:37
User: AskApache
Functions: echo read
6
SH
cat mod_log_config.c | shmore

or

shmore < mod_log_config.c

Most pagers like less, more, most, and others require additional processes to be loaded, additional cpu time used, and if that wasn't bad enough, most of them modify the output in ways that can be undesirable.

What I wanted was a "more" pager that was basically the same as running:

cat file

Without modifying the output and without additional processes being created, cpu used, etc. Normally if you want to scroll the output of cat file without modifying the output I would have to scroll back my terminal or screen buffer because less modifies the output.

After looking over many examples ranging from builtin cat functions created for csh, zsh, ksh, sh, and bash from the 80's, 90s, and more recent examples shipped with bash 4, and after much trial and error, I finally came up with something that satisifed my objective. It automatically adjusts to the size of your terminal window by using the LINES variable (or 80 lines if that is empty) so

This is a great function that will work as long as your shell works, so it will work just find if you are booted in single user mode and your /usr/bin directory is missing (where less and other pagers can be). Using builtins like this is fantastic and is comparable to how busybox works, as long as your shell works this will work.

One caveat/note: I always have access to a color terminal, and I always setup both the termcap and the terminfo packages for color terminals (and/or ncurses and slang), so for that reason I stuck the

tput setab 4; tput setaf 7

command at the beginning of the function, so it only runs 1 time, and that causes the -- SHMore -- prompt to have a blue background and bright white text.

This is one of hundreds of functions I have in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html">.bash_profile at http://www.askapache.com/">AskApache.com, but actually won't be included till the next update.

If you can improve this in any way at all please let me know, I would be very grateful! ( Like one thing I want is to be able to continue to the next screen by pressing any key instead of now having to press enter to continue)

APP=wine; if [ $(sudo apt-get --print-uris -y install $APP | sed -ne 's/^After this operation, \([0-9]\{1,\}\).*MB.*/\1/p') -gt 50 ]; then gnometris 2>/dev/null & sudo apt-get install $APP; else sudo apt-get install $APP; fi
2010-04-18 19:32:26
User: rkulla
Functions: install sed sudo
2

Change the APP variable's value to whatever you want to install. Depending on how fast your machine is, you'll want to adjust the value 50 to something else. You might also want to play a different game than Gnometris - just make sure it's a GUI game.

cat file1 ... fileN > combinedFile;
2010-04-17 01:00:04
User: GinoMan2440
Functions: cat
Tags: cat bash Linux
-4

the last person who posted used the most roundabout way to concatinate files, there's a reason there's a "conCATinate" command... Using this method, you also get to choose the order of the files, below another person just did *.txt > combined.txt which is fine but the order depends on the implementation of "cat" which is probably alphabetical order of filenames.

mplayer -playlist <(find $PWD -type f)
2010-04-17 00:20:08
User: rkulla
Functions: find
0

Press > or < to go to the next or previous track. Space to toggle play/pause, etc.

It creates a temp file descriptor. To see where the file descriptor gets created type: echo <(echo foo)

This works better than running find first, then piping to mplayer with xargs or something, because that won't let you use keyboard shortcuts.

cat *.txt >output.txt
ls | grep *.txt | while read file; do cat $file >> ./output.txt; done;
alias head='head -n $((${LINES:-`tput lines 2>/dev/null||echo -n 12`} - 2))'
26

Run the alias command, then issue

ps aux | head

and resize your terminal window (putty/console/hyperterm/xterm/etc) then issue the same command and you'll understand.

${LINES:-`tput lines 2>/dev/null||echo -n 12`}

Insructs the shell that if LINES is not set or null to use the output from `tput lines` ( ncurses based terminal access ) to get the number of lines in your terminal. But furthermore, in case that doesn't work either, it will default to using the deafault of 12 (-2 = 10).

The default for HEAD is to output the first 10 lines, this alias changes the default to output the first x lines instead, where x is the number of lines currently displayed on your terminal - 2. The -2 is there so that the top line displayed is the command you ran that used HEAD, ie the prompt.

Depending on whether your PS1 and/or PROMPT_COMMAND output more than 1 line (mine is 3) you will want to increase from -2. So with my prompt being the following, I need -7, or - 5 if I only want to display the commandline at the top. ( http://www.askapache.com/linux-unix/bash-power-prompt.html )

275MB/748MB

[7995:7993 - 0:186] 06:26:49 Thu Apr 08 [askapache@n1-backbone5:/dev/pts/0 +1] ~

In most shells the LINES variable is created automatically at login and updated when the terminal is resized (28 linux, 23/20 others for SIGWINCH) to contain the number of vertical lines that can fit in your terminal window. Because the alias doesn't hard-code the current LINES but relys on the $LINES variable, this is a dynamic alias that will always work on a tty device.

hb(){ sed "s/\($*\)/`tput setaf 2;tput setab 0;tput blink`\1`tput sgr0`/gI"; }
2010-04-07 08:45:26
User: AskApache
Functions: sed
-2
hb(){ sed "s/\($*\)/`tput setaf 2;tput setab 0;tput blink`\1`tput sgr0`/gI"; }

hb blinks, hc does a reverse color with background.. both very nice.

hc(){ sed "s/\($*\)/`tput setaf 0;tput setab 6`\1`tput sgr0`/gI"; }

Run this:

command ps -Hacl -F S -A f | hc ".*$PPID.*" | hb ".*$$.*"

Your welcome ;)

From my bash profile - http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

date +%A | cut -c $(( $(date +%A | wc -c) - 1 ))
2010-04-07 00:23:15
User: DaveQB
Functions: cut date wc
Tags: bash echo cut date wc
0

A command to find out what the day ends in. Can be edited slightly to find out what "any" output ends in.

NB: I haven't tested with weird and wonderful output.

function ends_in_y() { case $(date +%A) in *y ) true ;; * ) false ;; esac } ; ends_in_y && echo ok
2010-04-06 22:18:52
Functions: date echo false true
-1

The shell has perfectly adequate pattern matching for simple expressions.

function ends_in_y() { if [ `date +%A | sed -e 's/\(^.*\)\(.$\)/\2/'` == "y" ]; then echo 1; else echo 0; fi }
2010-04-06 20:14:34
User: allrightname
Functions: echo sed
-3

For those days when you need to know if something is happening because the day ends in "y".

du -cks * | sort -rn | while read size fname; do for unit in k M G T P E Z Y; do if [ $size -lt 1024 ]; then echo -e "${size}${unit}\t${fname}"; break; fi; size=$((size/1024)); done; done
wget randomfunfacts.com -O - 2>/dev/null | grep \<strong\> | sed "s;^.*<i>\(.*\)</i>.*$;\1;" | while read FUNFACT; do notify-send -t $((1000+300*`echo -n $FUNFACT | wc -w`)) -i gtk-dialog-info "RandomFunFact" "$FUNFACT"; done
2010-04-02 09:43:32
User: mtron
Functions: grep read sed wc wget
2

extension to tali713's random fact generator. It takes the output & sends it to notify-osd. Display time is proportional to the lengh of the fact.

PROMPT_COMMAND='if [ $RANDOM -le 3200 ]; then printf "\0337\033[%d;%dH\033[4%dm \033[m\0338" $((RANDOM%LINES+1)) $((RANDOM%COLUMNS+1)) $((RANDOM%8)); fi'
2010-04-01 06:52:32
User: hotdog003
Functions: printf
Tags: bash
24

Add this to a fiend's .bashrc.

PROMPT_COMMAND will run just before a prompt is drawn.

RANDOM will be between 0 and 32768; in this case, it'll run about 1/10th of the time.

\033 is the escape character. I'll call it \e for short.

\e7 -- save cursor position.

\e[%d;%dH -- move cursor to absolute position

\e[4%dm \e[m -- draw a random color at that point

\e8 -- restore position.

find . -type d -name '*[A-Z]*' -execdir bash -c '! test -f "$(echo "$0" | tr "[:upper:]" "[:lower:]")"' {} \; -execdir bash -c 'mv "$0" "$(echo "$0" | tr "[:upper:]" "[:lower:]")"' {} \;
while $8;do read n;[ $n = "$l" ]&&c=$(($c+1))||c=0;echo $c;l=$n;done
2010-03-31 00:41:08
User: florian
Functions: read
Tags: bash read Game
1

hold period (or whatever character) and hit enter after a second. You need to make the next line of periods the same length as the previous line... score starts at 0 and increase each time length of line is same.

wget randomfunfacts.com -O - 2>/dev/null | grep \<strong\> | sed "s;^.*<i>\(.*\)</i>.*$;\1;"
2010-03-30 23:49:30
User: tali713
Functions: grep sed wget
13

Though without infinite time and knowledge of how the site will be designed in the future this may stop working, it still will serve as a simple straight forward starting point.

This uses the observation that the only item marked as strong on the page is the single logical line that includes the italicized fact.

If future revisions of the page show failure, or intermittent failure, one may simply alter the above to read.

wget randomfunfacts.com -O - 2>/dev/null | tee lastfact | grep \<strong\> | sed "s;^.*<i>\(.*\)</i>.*$;\1;"

The file lastfact, can then be examined whenever the command fails.

du -kd | egrep -v "/.*/" | sort -n
2010-03-30 15:40:35
User: rmbjr60
Functions: du egrep sort
-1

Thanks for the submit! My alternative produces summaries only for directories. The original post additionally lists all files in the current directory. Sometimes the files, they just clutter up the output. Once the big directory is located, *then* worry about which file(s) are consuming so much space.

count="1" ; while true ; do read next ; if [[ "$next" = "$last" ]] ; then count=$(($count+1)) ; echo "$count" ; else count="1" ; echo $count ; fi ; last="$next" ; done
2010-03-30 04:02:29
User: dabom
Functions: echo read true
Tags: bash read Game
8

Really bored during class so I made this...

Basically, you hold period (or whatever) and hit enter after a second and you need to make the next line of periods the same length as the previous line...

My record was 5 lines of the same length.

It's best if you do it one handed with your pointer on period and ring on enter.

find ${PATH//:/ } -iname "*admin*" -executable -type f
2010-03-29 10:20:07
User: sanmiguel
Functions: find
Tags: bash find unix
1

While it seems (to me at least) a little counter-intuitive to filter on name first, this requires less work for find, as it allows it to immediately discount any files that do not match the name directly from the directory listing on disk. Querying against file attributes requires reading the file attributes, which is performed for all files matching any name based predicates.

svn stat -u | sort | sed -e "s/^M.*/\o033[31m&\o033[0m/" -e "s/^A.*/\o033[34m&\o033[0m/" -e "s/^D.*/\o033[35m&\o033[0m/"
2010-03-26 15:44:04
Functions: sed sort stat
Tags: bash svn sed
1

Use color escape sequences and sed to colorize the output of svn stat -u.

Colors: http://www.faqs.org/docs/abs/HTML/colorizing.html

svn stat characters: http://svnbook.red-bean.com/en/1.4/svn-book.html#svn.ref.svn.c.status

GNU Extensions for Escapes in Regular Expressions: http://www.gnu.org/software/sed/manual/html_node/Escapes.html

alias dush="du -sm *|sort -n|tail"
2010-03-26 10:18:57
User: funky
Functions: alias
28

sorts the files by integer megabytes, which should be enough to (interactively) find the space wasters. Now you can

dush

for the above output,

dush -n 3

for only the 3 biggest files and so on. It's always a good idea to have this line in your .profile or .bashrc

printf ${PATH//:/\\n}
ls -d $(echo ${PATH//:/ }) > /dev/null