Commands matching grep (2,284)

  • [Update! Thanks to a tip from ioggstream, I've fixed both of the bugs mentioned below.] You, yes, 𝙔𝙊𝙐, can be the terror of the Internet! Why use normal, boring bullet points in your text, when you could use a ROTATED HEAVY BLACK HEART BULLET (❥)!? (Which would also be an awesome band name, by the way).  This script makes it easy to find unusual characters from the command line. You can then cut and paste them or, if you're using a GTK application, type Control+Shift+U followed by the code point number (e.g., 2765) and then a SPACE.  USAGE: Put this script in a file (I called mine "ugrep") and make it executable. Run it from the command line like so,  ugrep heart  The output will look like this,  ☙ U+2619 REVERSED ROTATED FLORAL HEART BULLET ♡ U+2661 WHITE HEART SUIT ♥ U+2665 BLACK HEART SUIT ❣ U+2763 HEAVY HEART EXCLAMATION MARK ORNAMENT ❤ U+2764 HEAVY BLACK HEART ❥ U+2765 ROTATED HEAVY BLACK HEART BULLET ❦ U+2766 FLORAL HEART ❧ U+2767 ROTATED FLORAL HEART BULLET ⺖ U+2E96 CJK RADICAL HEART ONE ⺗ U+2E97 CJK RADICAL HEART TWO ⼼ U+2F3C KANGXI RADICAL HEART  You can, of course, use regular expressions. For example, if you are looking for the "pi" symbol, you could do this:  ugrep '\bpi\b'  REQUIREMENTS: Although this is written in Bash, it assumes you have Perl installed because it greps through the Perl Unicode character name module (/usr/lib/perl5/Unicode/CharName.pm). Note that it would not have made more sense to write this in Perl, since the CharName.pm module doesn't actually include a subroutine for looking up a character based on the description. (Weird.)  BUGS: In order to fit this script in the commandlinefu limits, a couple bugs were added. ① Astral characters beyond the BMP (basic multilingual plane) are not displayed correctly, but see below. ② Perl code from the perl module being grepped is sometimes extraneously matched.  MISFEATURES: Bash's printf cannot, given a Unicode codepoint, print the resulting character to the terminal. GNU's coreutils printf (usually "/usr/bin/printf") can do so, but it is brokenly pedantic about how many hexadecimal digits follow the escape sequence and will actually die with an error if you give the wrong number. This is especially annoying since Unicode code points are usually variable length with implied leading zeros. The CharNames.pm file represents BMP characters as 4 hexits, but astral characters as 5. In the actual version of this script that I use, I've kludged around this misfeature by zero-padding to 8 hexits like so,  /usr/bin/printf "\U$(printf "%08x" 0x$hex)"  TIP 1: The author recommends "xsel" for command line cut-and-paste. For example,  ugrep biohazard | xsel  TIP 2: In Emacs, instead of running this command in a subshell, you can type Unicode code points directly by pressing Control-Q first, but you'll likely want to change the default input from octal to hexadecimal. (setq read-quoted-char-radix 16).  TIP 3: Of course, if you're using X, and you want to type one of the more common unusual characters, it's easiest of all to do it with your Compose (aka Multi) key. For example, hitting [Compose] <3 types ♥. Show Sample Output


    12
    egrep -i "^[0-9a-f]{4,} .*$*" $(locate CharName.pm) | while read h d; do /usr/bin/printf "\U$(printf "%08x" 0x$h)\tU+%s\t%s\n" $h "$d"; done
    hackerb9 · 2010-12-31 16:47:59 15

  • 11
    lsof -P | grep ':3000'
    thisduck · 2009-03-23 18:41:24 11
  • Stop tormenting the poor animal cat. See http://sial.org/howto/shell/useless-cat/. Edit: replaced sort | uniq by sort -u


    11
    complete -W "$(echo $(grep '^ssh ' .bash_history | sort -u | sed 's/^ssh //'))" ssh
    0x89 · 2009-07-25 23:07:25 56
  • It identifies the parents of the Zombie processes and kill them. So the new parent of orphan Zombies will be the Init process and he is already waiting for reaping them. Be careful! It may also kill your useful processes just because they are not taking care and waiting for their children (bad parents!). Show Sample Output


    11
    kill -9 `ps -xaw -o state -o ppid | grep Z | grep -v PID | awk '{print $2}'`
    khashmeshab · 2010-10-27 07:29:14 12
  • My key is the anonymous one, is good for 50 post an hour with a maximun number of uploads a day, probably will run out, if that happend you can get a free key at the site. Show Sample Output


    11
    imgur(){ $*|convert label:@- png:-|curl -F "image=@-" -F "key=1913b4ac473c692372d108209958fd15" http://api.imgur.com/2/upload.xml|grep -Eo "<original>(.)*</original>" | grep -Eo "http://i.imgur.com/[^<]*";}
    dzup · 2011-09-23 05:42:58 14
  • Get the PID of a process by name Show Sample Output


    11
    pgrep command_name
    dstahlke · 2009-08-15 17:03:57 8
  • Surround the first letter of what you are grepping with square brackets and you won't have to spawn a second instance of grep -v. You could also use an alias like this (albeit with sed): alias psgrep='ps aux | grep $(echo $1 | sed "s/^\(.\)/[\1]/g")'


    10
    ps aux | grep [h]ttpd
    abcde · 2009-02-10 02:59:20 16
  • Pump up the chatter, run this script on a regular basis to listen to your twitter timeline. This is a rough first cut using several cli clips I have spotted around. There is no facility to not read those things already read to you. This could also easily be put in a loop for timed onslaught from the chatterverse, though I think it might violate several pointsof the Geneva Convention UPDATE - added a loop, only reads the first 6 twits, and does this every 5 mins. Show Sample Output


    10
    while [ 1 ]; do curl -s -u username:password http://twitter.com/statuses/friends_timeline.rss|grep title|sed -ne 's/<\/*title>//gp' | head -n 6 |festival --tts; sleep 300;done
    tomwsmf · 2009-02-20 20:20:21 17

  • 10
    while true; do X=$Y; sleep 1; Y=$(ifconfig eth0|grep RX\ bytes|awk '{ print $2 }'|cut -d : -f 2); echo "$(( Y-X )) bps"; done
    stuntdawg · 2009-03-27 08:26:39 10
  • doesn't do case-insensitive filenames like iname but otherwise likely to be faster


    10
    grep -r --include="*.[ch]" pattern .
    sitaram · 2009-08-13 01:41:12 17
  • Just refining last proposal for this check, showing awk power to make more complex math (instead /1024/1024, 2^20). We don't need declare variable before run lsof, because $(command) returns his output. Also, awk can perform filtering by regexp instead to call grep. I changed the 0.0000xxxx messy output, with a more readable form purging all fractional numbers and files less than 1 MB. Show Sample Output


    10
    lsof -p $(pidof firefox) | awk '/.mozilla/ { s = int($7/(2^20)); if(s>0) print (s)" MB -- "$9 | "sort -rn" }'
    tzk · 2010-01-13 22:45:53 7
  • I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server. So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg. Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time. Show Sample Output


    10
    sh -c 'S=askapache R=htaccess; find . -mount -type f|xargs -P5 -iFF grep -l -m1 "$S" FF|xargs -P5 -iFF sed -i -e "s%${S}%${R}%g" FF'
    AskApache · 2009-10-02 05:03:10 7
  • Simply more email-adresses matched Show Sample Output


    10
    grep -Eio '([[:alnum:]_.-]+@[[:alnum:]_.-]+?\.[[:alpha:].]{2,6})'
    fooBier · 2009-11-22 21:14:49 7
  • similar to the previous command, but with more friendly output (tested on linux)


    10
    strace -ff -e write=1,2 -s 1024 -p PID 2>&1 | grep "^ |" | cut -c11-60 | sed -e 's/ //g' | xxd -r -p
    systemj · 2010-04-23 16:22:17 4
  • Not as taxing on the CPU.


    10
    while [ true ]; do head -n 100 /dev/urandom; sleep .1; done | hexdump -C | grep "ca fe"
    campassi · 2010-10-05 16:23:31 5
  • This Anti-TarBomb function makes it easy to unpack a .tar.gz without worrying about the possibility that it will "explode" in your current directory. I've usually always created a temporary folder in which I extracted the tarball first, but I got tired of having to reorganize the files afterwards. Just add this function to your .zshrc / .bashrc and use it like this; atb arch1.tar.gz and it will create a folder for the extracted files, if they aren't already in a single folder. This only works for .tar.gz, but it's very easy to edit the function to suit your needs, if you want to extract .tgz, .tar.bz2 or just .tar. More info about tarbombs at http://www.linfo.org/tarbomb.html Tested in zsh and bash. UPDATE: This function works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in zsh (not working in bash): atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t(ar.gz||ar.bz2||gz||bz||ar)} && tar xf $1 -C ${1%.t(ar.gz||ar.bz2||gz||bz||ar)}; fi ;} UPDATE2: From the comments; bepaald came with a variant that works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in bash: atb() {shopt -s extglob ; l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)} && tar xf $1 -C ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)}; fi ; shopt -u extglob} Show Sample Output


    10
    atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.tar.gz} && tar xf $1 -C ${1%.tar.gz}; fi ;}
    elfreak · 2010-10-16 05:50:32 8
  • 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.


    10
    if [[ ":$PATH:" != *":$dir:"* ]]; then PATH=${PATH}:$dir; fi
    dmmst19 · 2013-08-11 01:19:13 19
  • Backups all MySQL databases to individual files. Can be put into a script that grabs current date so you have per day backups.


    9
    for I in `echo "show databases;" | mysql | grep -v Database`; do mysqldump $I > "$I.sql"; done
    ruedu · 2009-02-16 16:41:05 791
  • Very useful set of commands to know when your file system was created. Show Sample Output


    9
    df / | awk '{print $1}' | grep dev | xargs tune2fs -l | grep create
    Kaio · 2009-02-16 18:45:03 888
  • grep -o puts each occurrence in a separate line


    9
    $ grep -or string path/ | wc -l
    ioggstream · 2009-07-16 12:50:59 7
  • Adapted using your usefull comments !


    9
    grep -e `date +%Y-%m-%d` /var/log/dpkg.log | awk '/install / {print $4}' | uniq | xargs apt-get -y remove
    skygreg · 2010-01-12 09:42:22 11
  • This will calculate the your commandlinefu votes (upvotes - downvotes). Hopefully this will boost my commandlinefu points. Show Sample Output


    9
    username=matthewbauer; curl -s http://www.commandlinefu.com/commands/by/$username/json | tr '{' '\n' | grep -Eo ',"votes":"[0-9\-]+","' | grep -Eo '[0-9\-]+' | tr '\n' '+' | sed 's/+$/\n/' | bc
    matthewbauer · 2010-02-14 04:32:36 11
  • mixing tabs and spaces for indentation in python would confuse the python interpreter, to avoid that, check if the file has any tab based indentation. "^V" => denotes press control + v and press tab within quotes. cat improper_indent.py class Tux(object): print "Hello world.." grep " " improper_indent.py print "Hello world.."


    9
    grep "^V<TAB>" your_file
    sathyz · 2010-03-01 08:46:02 15

  • 9
    curl http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/[0-2500:25] | grep -v _curl_ > comfu.txt
    Neo23x0 · 2010-04-01 08:46:20 39
  • I found this command on a different site and thought you guy might enjoy it. Just change "YOURSEARCH" to what ever you want to search. Example, "Linux Commands"


    9
    Q="YOURSEARCH"; GOOG_URL="http://www.google.com/search?q="; AGENT="Mozilla/4.0"; stream=$(curl -A "$AGENT" -skLm 10 "${GOOG_URL}\"${Q/\ /+}\"" | grep -oP '\/url\?q=.+?&amp' | sed 's/\/url?q=//;s/&amp//'); echo -e "${stream//\%/\x}"
    techie · 2013-04-03 09:56:41 12
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