Commands tagged Linux UNIX (21)

  • find . -type f -iname '*.flac' # searches from the current folder recursively for .flac audio files | # the output (a .flac audio files with relative path from ./ ) is piped to while read FILE; do FILENAME="${FILE%.*}"; flac -cd "$FILE" | lame -b 192 - "${FILENAME}.mp3"; done # for each line on the list: # FILE gets the file with .flac extension and relative path # FILENAME gets FILE without the .flac extension # run flac for that FILE with output piped to lame conversion to mp3 using 192Kb bitrate Show Sample Output


    8
    find . -type f -iname '*.flac' | while read FILE; do FILENAME="${FILE%.*}"; flac -cd "$FILE" | lame -b 192 - "${FILENAME}.mp3"; done
    paulochf · 2010-08-15 19:02:19 2
  • This command can be used to extract the title defined in HTML pages


    3
    sed -n 's/.*<title>\(.*\)<\/title>.*/\1/ip;T;q' file.html
    octopus · 2010-04-19 07:41:10 3

  • 3
    rpm -q -a --qf '%10{SIZE}\t%{NAME}\n' | sort -k1,1n
    octopus · 2010-04-19 07:44:49 7
  • Usage: google "[search string]" Example: google "something im searching for" This will launch firefox and execute a google search in a new tab with the provided search string. You must provide the path to your Firefox binary if using cygwin to $ff or create an alias like follows: alias firefox='/cygdrive/c/Program Files (x86)/Mozilla Firefox/firefox.exe' Most Linux flavors with Firefox installed will use just ff="firefox" and even OSX.


    3
    google() { gg="https://www.google.com/search?q="; ff="firefox"; if [[ $1 ]]; then "$ff" -new-tab "$gg"$(echo ${1//[^a-zA-Z0-9]/+}); else echo 'Usage: google "[seach term]"'; fi }
    lowjax · 2013-08-01 22:21:53 11
  • Uses the shell builtin `declare` with the '-f' flag to output only functions to grep out only the function names. You can use it as an alias or function like so: alias shfunctions="builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'" shfunctions () { builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'; } Show Sample Output


    2
    builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'
    sciro · 2018-07-23 05:24:04 31

  • 1
    su - $user -c <command>
    octopus · 2010-04-16 13:17:02 2
  • You can do some boolean logic like A or B then C else D using or : || and : && So you can do some : # false || false && echo true || echo false false # true || false && echo true || echo false true # false || true && echo true || echo false true # true || true && echo true || echo false true and so on ... I use it like : (ssh example.com 'test something') || $(ssh example.net 'test something') && echo ok || echo ko Show Sample Output


    1
    true || false && echo true || echo false
    Sizeof · 2010-04-20 09:17:08 3
  • Just the commands for the lvreduce I keep forgetting.


    1
    # umount /media/filesystem; e2fsck -f /dev/device ; resize2fs -p /dev/device 200G #actual newsize#;lvreduce --size 200G /dev/device; mount /media/filesystem; df -h /media/filesystem
    bbelt16ag · 2011-09-14 08:52:02 2
  • The command creates an alias called 'path', so it's useful to add it to your .profile or .bash_profile. The path command then prints the full path of any file, directory, or list of files given. Soft links will be resolved to their true location. This is especially useful if you use scp often to copy files across systems. Now rather then using pwd to get a directory, and then doing a separate cut and paste to get a file's name, you can just type 'path file' and get the full path in one operation. Show Sample Output


    1
    alias path="/usr/bin/perl -e 'use Cwd; foreach my \$file (@ARGV) {print Cwd::abs_path(\$file) .\"\n\" if(-e \$file);}'"
    espider1 · 2012-01-18 01:40:05 3
  • Lots of scripts show you how to use socat to send an email to an SMTP server; this command actually emulates an SMTP server! It assumes the client is only sending to one recipient, and it's not at all smart, but it'll capture the email into a log file and the client will stop retrying. I used this to diagnose what emails were being sent by cron and subsequently discarded, but you can use it for all sorts of things. Show Sample Output


    1
    socat TCP4-LISTEN:25,fork EXEC:'bash -c \"echo 220;sleep 1;echo 250;sleep 1;echo 250;sleep 1;echo 250;sleep 1;echo 354;sleep 1;echo 250; timeout 5 cat >> /tmp/socat.log\"'
    pfudd · 2014-11-26 21:14:05 8
  • Change open-command and type to suit your needs. One example would be to open the last .jpg file with Eye Of Gnome: eog $(ls -rt *.jpg | tail -n 1)


    0
    open-command $(ls -rt *.type | tail -n 1)
    RBerenguel · 2010-04-04 20:43:38 3
  • Replace "Master" with desired control name (e.g. Front, Earphone, PCM, etc.). Show Sample Output


    0
    amixer -c 0 set Master 100%
    thewarden · 2013-03-28 16:30:10 2
  • The directories are created in the local host with the same structure below of a remote base directory, including the 'basedir' in case that it does not exists. You must replace user and remotehost (or IP address) with your proper values ssh will ask for the password of the user in remotehost, unless you had included properly your hostname in the remote .ssh/known_hosts file. Show Sample Output


    0
    ssh user@remotehost "find basedir -type d" | xargs -I {} -t mkdir -p {}
    neomefistox · 2013-07-17 07:14:32 4
  • dumpfile is a CSV file, which its 1st field is a phone number in format CC+10 digits Empty lines are deleted, before the output in format "prefix,ocurrences" Show Sample Output


    0
    cut -d, -f1 /var/opt/example/dumpfile.130610_subscriber.csv | cut -c3-5 | sort | uniq -c | sed -e 's/^ *//;/^$/d' | awk -F" " '{print $2 "," $1}' > SubsxPrefix.csv
    neomefistox · 2013-07-17 07:58:56 2
  • Support several arguments. Show Sample Output


    0
    google() { gg="https://www.google.com/search?q=";q="";if [[ $1 ]]; then for arg in "$@" ; do q="$q+$arg"; done ; if [[ -f /usr/bin/chromium ]]; then chromium "$gg"$q; else firefox -new-tab "$gg"$q; fi else echo 'Usage: google "[seach term]"'; fi }
    LenuX · 2013-08-08 14:34:09 2
  • Appends 4 configuration lines to your ~/.inputrc which allow you to seach history taking into account the characters you have typed so far. It is taken straight form https://help.ubuntu.com/community/UsingTheTerminal Go there for a complete description (grep for "Incremental history searching"). Not sure about the limits of this (which OS's/terminals), but probably anything unix/linux like will do. Changed my life :) Show Sample Output


    0
    echo '\n"\e[A": history-search-backward\n"\e[B": history-search-forward\n"\e[C": forward-char\n"\e[D": backward-char\n' >> ~/.inputrc
    temach · 2015-01-15 09:47:49 5
  • Set's up ETH0 to use DHCP, easy way


    0
    ifconfig eth0 0.0.0.0 0.0.0.0 && dhclient eth dhcp
    rootshadow · 2016-02-09 10:55:40 8
  • This assumes there is only one result. Either tail your search for one result or add | head -n 1 before the closing bracket. You can also use locate instead of find, if you have locate installed and updated


    -1
    evince "$(find -name 'NameOfPdf.pdf')"
    RBerenguel · 2010-04-04 20:55:51 3
  • Returns any file in the folder which would be rejected by Gmail, if you were to send zipped version. (Yes, you could just zip it and knock the extension off and put it back on the other side, but for some people this just isn't a solution) Show Sample Output


    -1
    find | egrep "\.(ade|adp|bat|chm|cmd|com|cpl|dll|exe|hta|ins|isp|jse|lib|mde|msc|msp|mst|pif|scr|sct|shb|sys|vb|vbe|vbs|vxd|wsc|wsf|wsh)$"
    poulter7 · 2010-11-23 16:53:55 8

  • -2
    /sbin/ifconfig|grep -B 1 inet |head -1 | awk '{print $5}'
    octopus · 2010-04-22 06:35:29 5
  • Ever need to erase the contents of a file and start over from scratch? This easy command allows you to do so. Be warned! This will immediately erase all the contents of your file and start you over from scratch (i.e. your file will be at 0 bytes, like if you touch a file). Show Sample Output


    -3
    > [filename]
    bbbco · 2011-05-18 14:59:02 5

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Print every Nth line
Sometimes commands give you too much feedback. Perhaps 1/100th might be enough. If so, every() is for you. $ my_verbose_command | every 100 will print every 100th line of output. Specifically, it will print lines 100, 200, 300, etc If you use a negative argument it will print the *first* of a block, $ my_verbose_command | every -100 It will print lines 1, 101, 201, 301, etc The function wraps up this useful sed snippet: $ ... | sed -n '0~100p' don't print anything by default $ sed -n starting at line 0, then every hundred lines ( ~100 ) print. $ '0~100p' There's also some bash magic to test if the number is negative: we want character 0, length 1, of variable N. $ ${N:0:1} If it *is* negative, strip off the first character ${N:1} is character 1 onwards (second actual character).

Generate a random password 30 characters long
The pwgen program generates passwords which are designed to be easily memorized by humans, while being as secure as possible. Human-memorable passwords are never going to be as secure as completely completely random passwords. [from pwgen man page]

Exclude svn directories with grep
exclude-dir option requires grep 2.5.3

recursively change file name from uppercase to lowercase (or viceversa)
Example of zsh globing, glob qualifier, and substitution: -Q state that the parameter will contain a glob qualifier. (**/)(*) is recursive (.) is our glob qualifier, with states the match is a file "." The first parameter $1, is then substituted with $2 but with lowercasing '(L)' ... a (U) would of course be from lower to upper.

Get size of terminal
See the cols and lines and make sure the console it correctly configured for the screen size.

Google Spell Checker
I took matthewbauer's cool one-liner and rewrote it as a shell function that returns all the suggestions or outputs "OK" if it doesn't find anything wrong. It should work on ksh, zsh, and bash. Users that don't have tee can leave that part off like this: $spellcheck(){ typeset y=$@;curl -sd "$y" https://google.com/tbproxy/spell|sed -n '/s="[1-9]"/{s/]*>/ /g;s/\t/ /g;s/ *\(.*\)/Suggestions: \1\n/g;p}';}

Tired of switching between proxy and no proxy? here's the solution.
Replace 10.0.0.0/8 with your largest local subnet. replace 10.1.1.123:3128 with your proxy information.. Note this only works with a proxy server configured for passive setup.. Now your firefox transparently proxy's stuff destined outside your network.. and Doesn't proxy stuff inside your network. as well as all your other favorite web applications. curl, wget, aria2 ect.

To create files with specific permission:

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Facebook Email Scraper
(Apparently it is too long so I put it in sample output, I hope that is OK.) Run the long command (or put it in your .bashrc) in sample output then run: $ fbemailscraper YourFBEmail Password Voila! Your contacts' emails will appear. Facebook seems to have gotten rid of the picture encoding of emails and replaced it with a text based version making it easy to scrape! Needs curl to run and it was made pretty quickly so there might be bugs.


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