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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

Top Tags



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands tagged bash from sorted by
Terminal - Commands tagged bash - 732 results
rp() { local p; eval p=":\$$1:"; export $1=${p//:$2:/:}; }; ap() { rp "$1" "$2"; eval export $1=\$$1$2; }; pp() { rp "$1" "$2"; eval export $1=$2:\$$1; }
2010-07-15 18:52:01
User: cout
Functions: eval export

I used to do a lot of path manipulation to set up my development environment (PATH, LD_LIBRARY_PATH, etc), and one part of my environment wasn't always aware of what the rest of the environment needed in the path. Thus resetting the entire PATH variable wasn't an option; modifying it made sense.

The original version of the functions used sed, which turned out to be really slow when called many times from my bashrc, and it could take up to 10 seconds to login. Switching to parameter substitution sped things up significantly.

The commands here don't clean up the path when they are done (so e.g. the path gets cluttered with colons). But the code is easy to read for a one-liner.

The full function looks like this:

remove_path() { eval PATHVAL=":\$$1:" PATHVAL=${PATHVAL//:$2:/:} # remove $2 from $PATHVAL PATHVAL=${PATHVAL//::/:} # remove any double colons left over PATHVAL=${PATHVAL#:} # remove colons from the beginning of $PATHVAL PATHVAL=${PATHVAL%:} # remove colons from the end of $PATHVAL export $1="$PATHVAL" } append_path() { remove_path "$1" "$2" eval PATHVAL="\$$1" export $1="${PATHVAL}:$2" } prepend_path() { remove_path "$1" "$2" eval PATHVAL="\$$1" export $1="$2:${PATHVAL}" }

I tried using regexes to make this into a cleaner one-liner, but remove_path ended up being cryptic and not working as well:

rp() { eval "[[ ::\$$1:: =~ ^:+($2:)?((.*):$2:)?(.*):+$ ]]"; export $1=${BASH_REMATCH[3]}:${BASH_REMATCH[4]}; };
alias dush="du -xsm * | sort -n | awk '{ printf(\"%4s MB ./\",\$1) ; for (i=1;i<=NF;i++) { if (i>1) printf(\"%s \",\$i) } ; printf(\"\n\") }' | tail"
2010-07-15 10:38:27
User: dopeman
Functions: alias

Essentially the same as funky's alias, but will not traverse filesystems and has nicer formatting.

cut -f 1 three-column.txt > first-column.txt
2010-07-11 10:13:45
User: postrational
Functions: cut

There is a common command for outputting a field or list of fields from each line in a file. Why wouldn't you just use cut?

variable="foo" && sed 's/bar/'$variable'/g' $variable.conf >> $variable.temp && sed '1,5d' $variable.temp && mv $variable.temp $variable.conf
2010-07-09 22:12:51
User: jdorfman
Functions: mv sed
Tags: bash sed nginx

I wrote this script to speed up Nginx configs. This (long) one liner can be run via BASH. You will see that we set a variable in bash called 'foo' and the streamline editor (sed) finds 'bar' in 'foo.conf' next it writes that output to a temp file (foo.temp) and removes the first 5 lines (that aren't needed in this case) & lastly it moves (overwrites) foo.temp to foo.conf

awk '{print $1}' < three-column.txt > first-column.txt
while read col1 col23; do echo $col1; done < three-column.txt > first-column.txt
while read l; do echo ${l%% *}; done < three-column-list.txt > only-first-column.txt
2010-07-09 03:42:56
User: zed
Functions: echo read

The above is an example of grabbing only the first column. You can define the start and end points specifically by chacater position using the following command:

while read l; do echo ${l:10:40}; done < three-column-list.txt > column-c10-c40.txt

Of course, it doesn't have to be a column, or extraction, it can be replacement

while read l; do echo ${l/foo/bar}; done < list-with-foo.txt > list-with-bar.txt

Read more about parameter expansion here:


Think of this as an alternative to awk or sed for file operations

for f in t1.bmp t2.jpg t3.tga; do echo ${f%.*}.png; done
2010-07-09 00:38:53
User: zed
Functions: echo

The above is just a prove of concept based around the nested bash substitution. This could be useful in situations where you're in a directory with many filetypes but you only want to convert a few.

for f in *.bmp *.jpg *.tga; do convert $f ${f%.*}.png; done

or you can use ls | egrep to get more specific... but be warned, files with spaces will cause a ruckus with expansion but the bash for loop uses a space delimited list.

for f in $(ls | egrep "bmp$|jpg$|tga$"); do convert $f ${f%.*}.png; done

I'm guessing some people will still prefer doing it the sed way but I thought the concept of this one was pretty neat. It will help me remember bash substitutions a little better :-P

__disown(){ local cmd=$1 ; shift ; $cmd "$@" &> /dev/null &disown }; for i in gvim ; do alias $i="__disown $i"; done
2010-07-07 20:46:45
User: smolav
Functions: alias shift
Tags: bash function

Define commands that you always invoke with an appended '&disown'. In the example:

gvim foo.txt

will open gvim dettached from the current terminal.

filterous -dntb --tag Bash < bookmarks.xml
2010-07-07 07:42:11
User: l0b0

You can install filterous with

sudo apt-get install libxslt1-dev; sudo easy_install -U filterous
alias histdel='history -d $((HISTCMD-2)) && history -d $((HISTCMD-1))'
2010-07-02 00:20:44
Functions: alias

I rarely need this, but I have a hard time remembering the command when I need it.

Admit it. This has happened to you. Yes this is bad, and you better clean up now.

Borrowed from http://thoughtsbyclayg.blogspot.com/2008/02/how-to-delete-last-command-from-bash.html

bsro3 () { P=`pwd`; S=$1; R=$2; ls *.odt > /dev/null 2>&1; if [[ $? -ne 0 ]]; then exit 1; fi; for i in *.odt; do mkdir ${P}/T; cd ${P}/T; unzip -qq "$P"/"$i"; sed -i "s/$S/$R/" ${P}/T/content.xml; zip -qq -r "$P"/"$i" *; cd ${P}; rm -rf ${P}/T; done; }
2010-06-30 04:43:54
User: danpos
Functions: cd exit ls mkdir rm sed

This function does a batch edition of all OOO3 Writer files in current directory. It uses sed to search a FOO pattern into body text of each file, then replace it to foo pattern (only the first match) . I did it because I've some hundreds of OOO3 Writer files where I did need to edit one word in each ones and open up each file in OOO3 gui wasn't an option. Usage: bsro3 FOO foo

for code in {0..255}; do echo -e "\e[38;05;${code}m $code: Test"; done
2010-06-19 02:14:42
User: scribe
Functions: echo
Tags: bash color colors

Same as http://www.commandlinefu.com/commands/view/5876, but for bash.

This will show a numerical value for each of the 256 colors in bash. Everything in the command is a bash builtin, so it should run on any platform where bash is installed. Prints one color per line. If someone is interested in formatting the output, paste the alternative.

L(){ l=`builtin printf %${2:-$COLUMNS}s` && echo -e "${l// /${1:-=}}"; }

One of the first functions programmers learn is how to print a line. This is my 100% bash builtin function to do it, which makes it as optimal as a function can be. The COLUMNS environment variable is also set by bash (including bash resetting its value when you resize your term) so its very efficient. I like pretty-output in my shells and have experimented with several ways to output a line the width of the screen using a minimal amount of code. This is like version 9,000 lol.

This function is what I use, though when using colors or other terminal features I create separate functions that call this one, since this is the lowest level type of function. It might be better named printl(), but since I use it so much it's more optimal to have the name contain less chars (both for my programming and for the internal workings).

If you do use terminal escapes this will reset to default.

tput sgr0

For implementation ideas, check my


2010-06-12 02:48:27
User: dbbolton
Tags: history bash zsh

'n' is a non-negative integer. Using 0 will expand to the name of the previous command.

statt(){ C=c;stat --h|sed '/Th/,/NO/!d;/%/!d'|while read l;do p=${l/% */};[ $p == %Z ]&&C=fc&&echo ^FS:^;echo "`stat -$C $p \"$1\"` ^$p^${l#%* }";done|column -ts^; }
2010-06-11 23:31:03
User: AskApache
Functions: column read sed

This shows every bit of information that stat can get for any file, dir, fifo, etc. It's great because it also shows the format and explains it for each format option.

If you just want stat help, create this handy alias 'stath' to display all format options with explanations.

alias stath="stat --h|sed '/Th/,/NO/!d;/%/!d'"

To display on 2 lines:

( F=/etc/screenrc N=c IFS=$'\n'; for L in $(sed 's/%Z./%Z\n/'<<<`stat --h|sed -n '/^ *%/s/^ *%\(.\).*$/\1:%\1/p'`); do G=$(echo "stat -$N '$L' \"$F\""); eval $G; N=fc;done; )

For a similarly powerful stat-like function optimized for pretty output (and can sort by any field), check out the "lll" function


From my .bash_profile ->


find $PWD -maxdepth 1 -printf '%.5m %10M %#9u:%-9g %#5U:%-5G [%AD | %TD | %CD] [%Y] %p\n'

I love this function because it tells me everything I want to know about files, more than stat, more than ls. It's very useful and infinitely expandable.

find $PWD -maxdepth 1 -printf '%.5m %10M %#9u:%-9g %#5U:%-5G [%AD | %TD | %CD] [%Y] %p\n' | sort -rgbS 50%

00761 drwxrw---x askapache:askapache 777:666 [06/10/10 | 06/10/10 | 06/10/10] [d] /web/cg/tmp

The key is:

# -printf '%.5m %10M %#9u:%-9g %#5U:%-5G [%AD | %TD | %CD] [%Y] %p\n'

which believe it or not took me hundreds of tweaking before I was happy with the output.

You can easily use this within a function to do whatever you want.. This simple function works recursively if you call it with -r as an argument, and sorts by file permissions.

lsl(){ O="-maxdepth 1";sed -n '/-r/!Q1'<<<$@ &&O=;find $PWD $O -printf '%.5m %10M %#9u:%-9g %#5U:%-5G [%AD | %TD | %CD] [%Y] %p\n'|sort -rgbS 50%; }

Personally I'm using this function because:

lll () { local a KS="1 -r -g"; sed -n '/-sort=/!Q1' <<< $@ && KS=`sed 's/.*-sort=\(.*\)/\1/g'<<<$@`; find $PWD -maxdepth 1 -printf '%.5m %10M %#9u:%-9g %#5U:%-5G [%AD | %TD | %CD] [%Y] %p\n'|sort -k$KS -bS 50%; }

# i can sort by user

lll -sort=3

# or sort by group reversed

lll -sort=4 -r

# and sort by modification time

lll -sort=6

If anyone wants to help me make this function handle multiple dirs/files like ls, go for it and I would appreciate it.. Something very minimal would be awesome.. maybe like:

for a; do lll $a; done

Note this uses the latest version of GNU find built from source, easy to build from gnu ftp tarball. Taken from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

alias sorth='sort --help|sed -n "/^ *-[^-]/s/^ *\(-[^ ]* -[^ ]*\) *\(.*\)/\1:\2/p"|column -ts":"'

Once you get into advanced/optimized scripts, functions, or cli usage, you will use the sort command alot. The options are difficult to master/memorize however, and when you use sort commands as much as I do (some examples below), it's useful to have the help available with a simple alias. I love this alias as I never seem to remember all the options for sort, and I use sort like crazy (much better than uniq for example).

# Sorts by file permissions

find . -maxdepth 1 -printf '%.5m %10M %p\n' | sort -k1 -r -g -bS 20%

00761 drwxrw---x ./tmp

00755 drwxr-xr-x .

00701 drwx-----x ./askapache-m

00644 -rw-r--r-- ./.htaccess

# Shows uniq history fast

history 1000 | sed 's/^[0-9 ]*//' | sort -fubdS 50%

exec bash -lxv

export TERM=putty-256color

Taken from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

acpi -V
IFS=`echo -en "\n\b"`; for i in $(curl http://feeds.digg.com/digg/container/technology/popular.rss | grep '<title>' | sed -e 's#<[^>]*>##g' | tail -n10); do echo $i; echo $i | sed 's/^/Did you hear about /g' | say; sleep 30; done
2010-06-07 22:16:19
User: echosedawk
Functions: echo grep sed sleep tail
Tags: bash sed curl osx

Instead of having someone else read you the Digg headlines, Have OSX do it. Requires Curl+Sed+Say. This could probably be easily modified to use espeak for Linux.

cowsay `fortune` | toilet --metal -f term
2010-06-03 21:48:54

Get colorful fortunes dictated by an ASCII cow. For full enjoyment you'll need to have color setup enabled for your terminal.

declare -F | cut -d ' ' -f 3
while [ 1 -lt 2 ]; do i=0; COL=$((RANDOM%$(tput cols)));ROW=$((RANDOM%$(tput cols)));while [ $i -lt $COL ]; do tput cup $i $ROW;echo -e "\033[1;34m" $(cat /dev/urandom | head -1 | cut -c1-1) 2>/dev/null ; i=$(expr $i + 1); done; done
2010-05-28 16:07:56
User: dave1010
Functions: cat cut expr head tput

Same as original, but works in bash

for d in $(find . -maxdepth 1 -type d -name '[^.]*'); do cd "$d"; svn up; cd ..; done
2010-05-28 10:09:19
User: udog
Functions: cd find

If you have a directory with many working copies of various subversion projects and you want to update them all at once, this one may be for you.