All commands (14,187)

  • I must monitorize a couple of ftp servers every morning WITHOUT a port-scanner Instead of ftp'ing on 100 ftp servers manually to test their status I use this loop. It might be adaptable to other services, however it may require a 'logout' string instead of 'quit'. The file ftps.txt contains the full list of ftp servers to monitorize.


    1
    for host in $(cat ftps.txt) ; do if echo -en "o $host 21\nquit\n" |telnet 2>/dev/null |grep -v 'Connected to' >/dev/null; then echo -en "FTP $host KO\n"; fi done
    vlan7 · 2010-01-26 15:34:18 3
  • Recursive grep through directory for file.


    -5
    find directory/ |xargs grep -i "phrase"
    tuxtutorials · 2010-01-26 14:56:56 3
  • no loop, only one call of grep, scrollable ("less is more", more or less...)


    12
    ls /usr/bin | xargs whatis | grep -v nothing | less
    michelsberg · 2010-01-26 12:59:47 32
  • Useful for Maven multimodule projects, where you want to extract all packaged jar files.


    -3
    find . -iname "*.jar" -exec cp '{}' /tmp/ \;
    unixmonkey6754 · 2010-01-26 12:19:15 3
  • This command has been used to overwrite corrupted "entries" files of a corrupted subversion working copy. Note the --files-from input format.


    3
    rsync -vd --files-from=<(find . -name entries -print ) . ../target_directory
    samyboy · 2010-01-26 09:41:12 6
  • This command toggles the touchpad on and off, when it's on, the right side scroll strip (annoying) and the tap-clicking are disabled, you can change this by changing occurances of 2 in the command to 0. this whole command can then be given a keyboard shortcut so that the touchpad is disableable without using a special fn key (which linux doesn't recognize on some computers) or a seperate button.


    -3
    if [ $(synclient -l | grep TouchpadOff | awk '{print $3}') = "2" ]; then synclient TouchpadOff=1; elif [ $(synclient -l | grep TouchpadOff | awk '{print $3}') == "1" ]; then synclient TouchpadOff=2; else synclient TouchpadOff=2; fi
    GinoMan2440 · 2010-01-26 07:52:55 5

  • 1
    find . -maxdepth 1 -type d -exec 'mv "{}" "{}-old" && svnadmin create "{}" && svnadmin recover "{}-old" && svnadmin dump "{}-old" | svnadmin load "{}" && rm -rf "{}-old"' \;
    raspi · 2010-01-26 07:06:43 3

  • 7
    for i in $(ls /usr/bin); do whatis $i | grep -v nothing; done | more
    Abiden · 2010-01-26 06:15:54 7

  • -2
    7za x \*.zip
    andrew112358 · 2010-01-25 21:50:15 2
  • Traditionally we rewind a tape using this syntaxis: mt -f /dev/rmt/0cbn rewind Redirecting the dispositive to nothing as shown above is faster. Less typing is always better.


    2
    < /dev/rmt/0cbn
    vlan7 · 2010-01-25 20:32:38 3

  • -1
    find . -maxdepth 1 -type f| xargs sha1sum | sed 's/^\(\w*\)\s*\(.*\)/\2 \1/' | while read LINE; do mv $LINE; done
    foremire · 2010-01-25 20:21:01 11
  • for example if you did a: ls -la /bin/ls then ls !$ is equivalent to doing a ls /bin/ls


    9
    !$
    ringlerun · 2010-01-24 17:59:52 23
  • running top command in batch mode. it is usefull if you want to redirect the output in a file. Show Sample Output


    2
    top -b -n 1
    r00t4u · 2010-01-24 16:17:30 5

  • 0
    dpkg -l | grep ^rc | awk '{print $2}' | sudo xargs dpkg -P
    kayowas · 2010-01-24 14:23:37 4
  • Use find's built-in ability to call programs. Alternatively, find -maxdepth 1 -type f -name "*.7z" -print0 | xargx -0 -n 1 7zr e would work, too.


    -1
    find -maxdepth 1 -type f -name "*.7z" -exec 7zr e '{}' ';'
    minnmass · 2010-01-23 19:50:10 4

  • 0
    find . -type f -exec stat \{\} \; | grep Modify: | awk '{a[$2]++}END{for(i in a){print i " : " a[i] }}' | sort
    pepin · 2010-01-23 07:55:16 6
  • Restores the keyboard so your partner who expects the keys to correspond to what they're labelled can type (in qwerty).


    -2
    setxkbmap us
    keturn · 2010-01-23 04:08:46 4
  • What to type to fix the keyboard when it's all qwerty and/or the modifier key to the left of the 'a' is doing something unexpected. In addition, I've also been known to use the altwin:meta_win and compose:ralt flags.


    0
    setxkbmap dvorak '' ctrl:nocaps
    keturn · 2010-01-23 04:04:59 3
  • A command to post a message to Twitter that includes your geo-location and a short URL. The link shortening service is provide by TinyURL, the geo-location service is provided by HostIP and the IP address lookup service is provided by AppSpot. This is an upgrade of an of one of my previous contributions: http://tinyurl.com/yd2xtzv.


    4
    curl --user "USERNAME:PASSWORD" -d status="MESSAGE_GOES_HERE $(curl -s tinyurl.com/api-create.php?url=URL_GOES_HERE) $(curl -s api.hostip.info/get_html.php?ip=$(curl ip.appspot.com))" -d source="cURL" twitter.com/statuses/update.json -o /dev/null
    o0110o · 2010-01-23 02:21:57 11

  • -7
    scp /home/svnlabs.txt root@92.178.0.56:/home/
    bakhru · 2010-01-22 21:19:37 5

  • 10
    nmap -T4 -sP 192.168.2.0/24 && egrep "00:00:00:00:00:00" /proc/net/arp
    wincus · 2010-01-22 20:36:43 8

  • 3
    for file in *.7z; do 7zr e "$file"; done
    jmcantrell · 2010-01-22 18:42:20 11
  • Connect EC2 server with public keys "/root/.ec2/id_rsa-gsg-keypair" or "/root/.ec2/keypair.pem"


    -2
    rsync -avvvz -e "ssh -i /root/.ec2/id_rsa-gsg-keypair" --archive --progress /root/.ec2/id_rsa-gsg-keypair root@ec2-75-101-212-113.compute-1.amazonaws.com:/root
    lalit241 · 2010-01-22 17:21:58 3
  • Upload file to remote server using SCP


    -9
    scp -P 22 /home/svnlabs.txt root@92.178.0.56:/home/svnlabs.txt
    lalit241 · 2010-01-22 17:21:07 3
  • Upload file to remote server using SCP


    -6
    scp -P 22 /home/svnlabs.txt root@92.178.0.56:/home/svnlabs.txt
    svnlabs · 2010-01-22 16:55:25 4
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list all files in a directory, sorted in reverse order by modification time, use file descriptors.
It's both silly, and infinitely useful. Especially useful in logfile directories where you want to know what file is being updated while troubleshooting.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

BASH: Print shell variable into AWK

See how many more processes are allowed, awesome!
There is a limit to how many processes you can run at the same time for each user, especially with web hosts. If the maximum # of processes for your user is 200, then the following sets OPTIMUM_P to 100. $ OPTIMUM_P=$(( (`ulimit -u` - `find /proc -maxdepth 1 \( -user $USER -o -group $GROUPNAME \) -type d|wc -l`) / 2 )) This is very useful in scripts because this is such a fast low-resource-intensive (compared to ps, who, lsof, etc) way to determine how many processes are currently running for whichever user. The number of currently running processes is subtracted from the high limit setup for the account (see limits.conf, pam, initscript). An easy to understand example- this searches the current directory for shell scripts, and runs up to 100 'file' commands at the same time, greatly speeding up the command. $ find . -type f | xargs -P $OPTIMUM_P -iFNAME file FNAME | sed -n '/shell script text/p' I am using it in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html especially for the xargs command. Xargs has a -P option that lets you specify how many processes to run at the same time. For instance if you have 1000 urls in a text file and wanted to download all of them fast with curl, you could download 100 at a time (check ps output on a separate [pt]ty for proof) like this: $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' I like to do things as fast as possible on my servers. I have several types of servers and hosting environments, some with very restrictive jail shells with 20processes limit, some with 200, some with 8000, so for the jailed shells my xargs -P10 would kill my shell or dump core. Using the above I can set the -P value dynamically, so xargs always works, like this. $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' If you were building a process-killer (very common for cheap hosting) this would also be handy. Note that if you are only allowed 20 or so processes, you should just use -P1 with xargs.

Count the total number of files in each immediate subdirectory
counts the total (recursive) number of files in the immediate (depth 1) subdirectories as well as the current one and displays them sorted. Fixed, as per ashawley's comment

for too many arguments by *
$ grep ERROR *.log -bash: /bin/grep: Argument list too long $ echo *.log | xargs grep ERROR /dev/null 20090119.00011.log:DANGEROUS ERROR

get total of inodes of root partition

A signal trap that logs when your script was killed and what other processes were running at that time
trap is the bash builtin that allows you to execute commands when the current script receives a particular signal. Uses $0 for the script name, $$ for the script PID, tee to output to STDOUT as well as a log file and ps to log other running processes.

take a look to command before action
add |sh when you agree the list, I often use that method to prevent typos in dangerous or long operations

Get gzip compressed web page using wget.
Like the original command, but the -f allows this one to succeed even if the website returns uncompressed data. From gzip(1) on the -f flag: If the input data is not in a format recognized by gzip, and if the --stdout is also given, copy the input data without change to the standard output: let zcat behave as cat.


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