All commands (14,187)

  • Remove trailing whitespaces (or tabs) from a text file

    This command is useful when you are programming, for example.


    -1
    sed -i 's/[ \t]\+$//g' file.txt
    elder · 2011-09-07 01:47:44 9
  • Show all groups user is a member of and other useful info


    -1
    net user USERNAME /domain
    shawn_abdushakur · 2014-01-02 20:22:46 7
  • my command for downloading delicious web links,

    just a alternative using a saved html file of all of my bookmarks. works well although it takes awhile.


    -1
    wget -r --wait=5 --quota=5000m --tries=3 --directory-prefix=/home/erin/Documents/erins_webpages --limit-rate=20k --level=1 -k -p -erobots=off -np -N --exclude-domains=del.icio.us,doubleclick.net -F -i ./delicious-20090629.htm
    bbelt16ag · 2009-07-02 01:46:21 7
  • CPU architecture details

    It works in every linux box Show Sample Output


    -1
    cat /proc/cpuinfo
    magicjohnson_ · 2010-09-24 09:27:58 3
  • OSX Terminal helper with tab completion, ssh tunneling, and now screen re-attach

    http://github.com/c3w/ash . a Ruby SSH helper script . reads a JSON config file to read host, FQDN, user, port, tunnel options . changes OSX Terminal profiles based on host 'type' USAGE: put 'ash' ruby script in your PATH modify and copy ashrc-dist to ~/.ashrc configure OSX Terminal profiles, such as "webserver", "development", etc run "ash myhostname" and away you go! v.2 will re-attach to a 'screen' named in your ~/.ashrc Show Sample Output


    -1
    ash prod<tab>
    c3w · 2012-05-12 19:51:02 8
  • ls


    -1
    ls
    yingkailiang · 2013-03-14 01:28:01 5
  • check your up to date delicious links.

    This commands queries the delicious api then runs the xml through xml2, grabs the urls cuts out the first two columns, passes through uniq to remove duplicates if any, and then goes into linkchecker who checks the links. the links go the blacklist in ~/.linkchecker/blacklist. please see the manual pages for further info peeps. I took me a few days to figure this one out. I how you enjoy it. Also don't run these api more then once a few seconds you can get banned by delicious see their site for info. ~updated for no recursive Show Sample Output


    -1
    curl -k https://Username:Password@api.del.icio.us/v1/posts/all?red=api | xml2| \grep '@href' | cut -d\= -f 2- | sort | uniq | linkchecker -r0 --stdin --complete -v -t 50 -F blacklist
    bbelt16ag · 2013-05-04 17:43:21 8
  • Find all files containing a word

    This is very similar to the first example except that it employs the 'exec' argument of the find command rather than piping the result to xargs. The second example is nice and tidy but different *NIXs may not have as capable a grep command.


    -1
    find . -name "*.php" -exec grep -il searchphrase {} \;
    unixmonkey7797 · 2010-01-16 05:09:30 4
  • identify big file

    first 10 big file


    -1
    du -s * | sort -nr | head
    chenge · 2010-05-13 12:21:22 4
  • Timelapse with ffmpeg (after symlinking pictures as per ffmpeg FAQ)


    -1
    ffmpeg -r 12 -i img%03d.jpg -sameq -s hd720 -vcodec libx264 -crf 25 OUTPUT.MP4
    brainstorm · 2013-05-04 18:46:36 9
  • hardcode dnsserver, no more rewriting of etc/resolv.conf

    The while loop is an overkill, it would be simpler to prevent the file to be modified. That said, none of the proposed solutions are such: a real one would go to the source of the problem.


    -1
    chkmod -w /etc/resolve.conf
    ntropia · 2018-05-14 16:25:47 158
  • Edit all files found having a specific string found by grep

    Make sure that find does not touch anything other than regular files, and handles non-standard characters in filenames while passing to xargs.


    -1
    find . -type f -exec grep -qi 'foo' {} \; -print0 | xargs -0 vim
    arcege · 2009-09-03 17:55:26 7
  • Pear install behind proxy

    Useful since "export http_proxy=blahblah:8080" doesn't seem to work with pear Show Sample Output


    -1
    pear config-set http_proxy http://myusername:mypassword@corporateproxy:8080
    KoRoVaMiLK · 2010-05-13 14:44:03 30
  • know which version of the program is installed on your Debian and derivatives

    Output: Version 3.2-0 (for example if you type # aptitude show bash | grep Vers Depends on the language of your distribution, because the name of the word "Version" in other languages may be different.


    -1
    aptitude show $PROGRAM | grep Vers
    aabilio · 2009-02-27 23:24:37 8
  • Get minimum, current, maximum possible resolution of Xorg


    -1
    xrandr -q | grep -w Screen
    hemanth · 2010-02-14 15:38:49 3
  • split a postscript file

    splits a postscript file into multiple postscript files. for each page of the input file one output file will be generated. The files will be numbered for example 1_orig.ps 2_orig.ps ... The psselect commad is part of the psutils package


    -1
    file=orig.ps; for i in $(seq `grep "Pages:" $file | sed 's/%%Pages: //g'`); do psselect $i $file $i\_$file; done
    damncool · 2010-09-24 19:44:32 4
  • A simple overview of memory usage refreshed at user designated intervals.

    This command shows a high level overview of system memory and usage refreshed in seconds. Change -n 10 to you desired refresh interval. Show Sample Output


    -1
    watch -n 10 free -m
    Darkstar · 2014-01-04 10:10:15 12
  • Find the full path of an already running process

    Uses the pid to get the full path of the process. Useful when you do not which command got picked from the path Show Sample Output


    -1
    readlink -f /proc/<pid>/cmdline
    naseer · 2009-05-26 10:09:03 23
  • Filenames ROT13

    This got a bit complicated, because I had to introduce an additional dot at the end that has to be removed again later.


    -1
    for each in *; do file="$each."; name=${file%%.*}; suffix=${file#*.}; mv "$each" "$(echo $name | rot13)${suffix:+.}${suffix%.}"; done
    hfs · 2010-03-20 16:11:12 6
  • Sort files in $PWD by year embedded anywhere in filename


    -1
    ls --color=never -1| grep -E "[0-9]{4}"|sed -re "s/^(.*)([0-9]{4})(.*)$/\2 \1\2\3/" | sort -r
    ysangkok · 2014-01-04 20:50:12 9
  • display only tcp


    -1
    netstat -4tnape
    gnuyoga · 2009-05-26 11:50:52 5
  • wget, tar xzvf, cd, ls

    Combines a few repetitive tasks when compiling source code. Especially useful when a hypen in a file-name breaks tab completion. 1.) wget source.tar.gz 2.) tar xzvf source.tar.gz 3.) cd source 4.) ls From there you can run ./configure, make and etc. Show Sample Output


    -1
    wtzc () { wget "$@"; foo=`echo "$@" | sed 's:.*/::'`; tar xzvf $foo; blah=`echo $foo | sed 's:,*/::'`; bar=`echo $blah | sed -e 's/\(.*\)\..*/\1/' -e 's/\(.*\)\..*/\1/'`; cd $bar; ls; }
    oshazard · 2010-01-17 11:25:47 3
  • Split a file into equal size chunks and archive to (e)mail account.

    This is just a little snippit to split a large file into smaller chunks (4mb in this example) and then send the chunks off to (e)mail for archival using mutt. I usually encrypt the file before splitting it using openssl: openssl des3 -salt -k <password> -in file.tgz -out file.tgz.des3 To restore, simply save attachments and rejoin them using: cat file.tgz.* > output_name.tgz and if encrypted, decrypt using: openssl des3 -d -salt -k <password> -in file.tgz.des3 -out file.tgz edit: (changed "g" to "e" for political correctness)


    -1
    split -b4m file.tgz file.tgz. ; for i in file.tgz.*; do SUBJ="Backup Archive"; MSG="Archive File Attached"; echo $MSG | mutt -a $i -s $SUBJ YourEmail@(E)mail.com
    tboulay · 2010-03-20 16:49:19 8
  • Find Out My Linux Distribution Name and Version


    -1
    if [ -x /etc/*-release ]; then cat /etc/*-release ; else cat /etc/*-version ; fi
    hugoeustaquio · 2011-06-22 14:09:24 3
  • Transfer files with rsync over ssh on a non-standard port.

    Transfer files with rsync over ssh on a non-standard port, showing a progress bar and resuming partial transfers.


    -1
    rsync -P -e 'ssh -p PORT' SRC DEST
    vickio · 2011-10-13 08:59:07 4
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Make changes in .bashrc immediately available

Display IP : Count of failed login attempts
The lastb command presents you with the history of failed login attempts (stored in /var/log/btmp). The reference file is read/write by root only by default. This can be quite an exhaustive list with lots of bots hammering away at your machine. Sometimes it is more important to see the scale of things, or in this case the volume of failed logins tied to each source IP. The awk statement determines if the 3rd element is an IP address, and if so increments the running count of failed login attempts associated with it. When done it prints the IP and count. The sort statement sorts numerically (-n) by column 3 (-k 3), so you can see the most aggressive sources of login attempts. Note that the ':' character is the 2nd column, and that the -n and -k can be combined to -nk. Please be aware that the btmp file will contain every instance of a failed login unless explicitly rolled over. It should be safe to delete/archive this file after you've processed it.

Generat a Random MAC address

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

password generator
make password randomly, default 8 chars, using bash3.X only, no external program.

clear current line

Print out a man page
man -t manpagename gives a postscript version of said man page. You then pipe it to ls, and assuming you have cups set up, it prints in your default printer.

Fix for error perl: warning: Setting locale failed.
Fix for ubuntu error: perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LANGUAGE = "en_GB:en", LC_ALL = (unset), LANG = "en_GB.UTF-8" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). locale: Cannot set LC_CTYPE to default locale: No such file or directory locale: Cannot set LC_MESSAGES to default locale: No such file or directory locale: Cannot set LC_ALL to default locale: No such file or directory

Clear terminal Screen

Netstat Connection Check
This command does a tally of concurrent active connections from single IPs and prints out those IPs that have the most active concurrent connections. VERY useful in determining the source of a DoS or DDoS attack.

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