All commands (14,187)

  • Stat each file in a directory

    This will run stat on each file in the directory. Show Sample Output


    1
    find -name `egrep -s '.' * | awk -F":" '{print $1}' | sort -u` -exec stat {} \;
    unixmonkey8594 · 2010-04-26 20:01:44 5
  • Simplest port scanner

    Very handy way to perform a host scan if you don't have nmap,ncat,nc ...or other tools installed locally. When executing a command on a /dev/tcp/$host/$port pseudo-device file, Bash opens a TCP connection to the associated socket and UDP connection when using /dev/udp/$host/$port.A simlpe way to get servers banner is to run this command "cat < /dev/tcp/localhost/25" , here you will get mail server's banner. NOTE: Bash, as packaged for Debian, does not support using the /dev/tcp and /dev/udp pseudo-device it's not enabled by default Because bash in Debian is compiled with ?disable-net-redirections. Show Sample Output


    4
    for p in {1..1023}; do(echo >/dev/tcp/localhost/$p) >/dev/null 2>&1 && echo "$p open"; done
    benyounes · 2010-04-26 18:09:22 41
  • Report full partitions from a cron

    Reports all local partitions having more than 90% usage. Just add it in a crontab and you'll get a mail when a disk is full. (sending mail to the root user must work for that) Show Sample Output


    2
    df -l | grep -e "9.%" -e "100%"
    dooblem · 2010-04-26 17:57:54 3
  • Get Lorum Ipsum random text from lorumipsum.com

    This will generate 3 paragraphs with random text. Change the 3 to any number. Show Sample Output


    5
    lynx -source http://www.lipsum.com/feed/xml?amount=3|perl -p -i -e 's/\n/\n\n/g'|sed -n '/<lipsum>/,/<\/lipsum>/p'|sed -e 's/<[^>]*>//g'
    houghi · 2010-04-26 17:26:44 5
  • Quickly share code or text from vim to others.

    Sprunge.us is a code/text sharing site like pastebin, but it is easy to post stuff from the command line. How it works: :w !command In vim, w writes the current tab to a file when a filename is given afterwards, but if !command is given, the output is piped to the stdin of command. curl -F "sprunge=<-" http://sprunge.us curl is an HTTP client. The -F option does an HTTP post to the given address. The data in the quotes is passed in the post. The "sprunge=" part sets up a fieldname - the part that follows is what is associated with the name. The "<" tells curl to send data from the file descriptor that follows it. The "-" in bash is a file descriptor that points to stdin instead of an actual file; in this case, stdin is being piped in from vim. After we send the HTTP post to sprunge.us, it will give back a url that points to the data you just sent. | xclip xclip is a utility that lets you put stuff in your clipboard or selection buffer. This part uses a bash pipe ( | ) to redirect the stdout of the previous command to the stdin of the next command. So, we're capturing the URL that curl gave us and putting it into the selection buffer, ready to paste into IRC or a forum. Notes: Of course, for this to work, you must have curl (which comes by default on most distroes), and xclip installed. When you share the url, you can append "?lang" to highlight and have line numbers. Check out http://sprunge.us/BZXV?log for line numbers and http://sprunge.us/BZXV?ruby for highlighting. If you prefer to use ctrl-v (paste from clipboard) instead of middle-click (paste from selection buffer), look up options on xclip - you can do that. Show Sample Output


    18
    :w !curl -F "sprunge=<-" http://sprunge.us | xclip
    shawnjgoff · 2010-04-25 00:43:37 33
  • Converting video file (.flv, .avi etc.) to .3gp

    ffmpeg -i = input file name -s = set frame size, qcif=176x144 -vcodec = force video codec -r = frame-rate [default = 25] -b = bit-rate [200 kb/s] -acodec = force audio codec -ab = audio bitrate in bits/s [64k] -ac = no. of audio channels [1] -ar = audio sampling frequency [44100 Hz] optional: -sameq = use same video quality as source (implies VBR) -f = force format -y = overwrite output files


    3
    ffmpeg -i input.avi -s qcif -vcodec h263 -r 20 -b 180k -acodec libfaac -ab 64k -ac 2 -ar 22050 output.3gp
    mariusbutuc · 2010-04-24 23:01:21 4
  • Opens vi/vim at pattern in file

    Open up vi or vim at the first instance of a pattern in [file]. Useful if you know where you want to be, like "PermitRootLogin" in sshd_config. Also, vi +10 [file] will open up a file at line 10. VERY useful when you get "error at line 10" type of output.


    25
    vi +/pattern [file]
    punkwalrus · 2010-04-24 22:15:12 7
  • see the TIME_WAIT and ESTABLISHED nums of the network

    see the TIME_WAIT and ESTABLISHED nums of the network Show Sample Output


    7
    netstat -n | awk '/^tcp/ {++B[$NF]} END {for(a in B) print a, B[a]}'
    healthly · 2010-04-24 12:11:52 4
  • Smart `cd`.. cd to the file directory if you try to cd to a file

    This little function will smarten 'cd'. If you try to cd into a file (which I guess we all have done), it cd's into the directory of that file instead. I had to use nesten if's, to get cd to still work with 'cd' (to get to $HOME), 'cd -' (to get to last directory), and 'cd foo\ bar'. Show Sample Output


    9
    cd() { if [ -z "$1" ]; then command cd; else if [ -f "$1" ]; then command cd $(dirname "$1"); else command cd "$1"; fi; fi; }
    xeor · 2010-04-23 19:17:43 6
  • Iterate through current directory + all subs for C++ header files and rank by # of comments

    This shows you which files are most in need of commenting (one line of output per file)


    1
    find ./ -name *.h -exec egrep -cH "// | /\*" {} \; | awk -F':' '{print $2 ":" $1}' | sort -gr
    blocky · 2010-04-23 19:00:07 3
  • intercept stdout/stderr of another process

    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
  • show ALL iptable rules

    show your current iptable rules from every available iptable table


    1
    for i in `cat /proc/net/ip_tables_names`; do iptables -nL -v --line-numbers -t $i ; done
    bw · 2010-04-23 13:53:49 9
  • Create a virtual disk (CD/DVD) in VirtualBox

    No comment... it's easy! Using the VBoxManage list and the switch 'hdds' or 'dvds' you can show the list of hard disks and DVD registered on the system.


    0
    VBoxManage openmedium dvd "/path/name.iso"
    0disse0 · 2010-04-23 06:56:42 5
  • How to create a vm in VirtualBox

    No comment: it's easy!


    -1
    VBoxManage createvm --name "vm-name" --ostype Ubuntu --register
    0disse0 · 2010-04-23 06:54:26 4
  • List the supported OS in VirtualBox

    If you want to know what OS are supported on "guest" machines on the Sun VirtualBox server.


    -1
    VBoxManage list ostypes
    0disse0 · 2010-04-23 06:50:42 8
  • Verify the virtual machine status

    where "cicciobox" is the name of your virtual machine in a Sun VirtualBox server


    -1
    VBoxManage showvminfo "cicciobox" --details
    0disse0 · 2010-04-23 06:45:29 3
  • Show the system properties in a Sun VirtualBox server

    How to show the system properties of a Sun VirtualBox server


    -1
    VBoxManage list systemproperties
    0disse0 · 2010-04-23 06:43:49 6
  • Run TOP in Color, split 4 ways for x seconds - the ultimate ps command. Great for init scripts

    One of my favorite ways to impress newbies (and old hats) to the power of the shell, is to give them an incredibly colorful and amazing version of the top command that runs once upon login, just like running fortune on login. It's pretty sweet believe me, just add this one-liner to your ~/.bash_profile -- and of course you can set the height to be anything, from 1 line to 1000! G=$(stty -g);stty rows $((${LINES:-50}/2));top -n1; stty $G;unset G Doesn't take more than the below toprc file I've added below, and you get all 4 top windows showing output at the same time.. each with a different color scheme, and each showing different info. Each window would normally take up 1/4th of your screen when run like that - TOP is designed as a full screen program. But here's where you might learn something new today on this great site.. By using the stty command to change the terminals internal understanding of the size of your terminal window, you force top to also think that way as well. # save the correct settings to G var. G=$(stty -g) # change the number of rows to half the actual amount, or 50 otherwise stty rows $((${LINES:-50}/2)) # run top non-interactively for 1 second, the output stays on the screen (half at least) top -n1 # reset the terminal back to the correct values, and clean up after yourself stty $G;unset G This trick from my [ http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html bash_profile ], though the online version will be updated soon. Just think what else you could run like this! Note 1: I had to edit the toprc file out due to this site can't handle that (uploads/including code). So you can grab it from [ http://www.askapache.com/linux-unix/bash-power-prompt.html my site ] Note 2: I had to come back and edit again because the links weren't being correctly parsed Show Sample Output


    3
    G=$(stty -g);stty rows $((${LINES:-50}/2));top -n1; stty $G;unset G
    AskApache · 2010-04-22 18:52:49 13
  • check the status of 'dd' in progress (OS X)

    "killall -USR1 dd" does not work in OS X for me. However, sending INFO instead of USR1 works. Show Sample Output


    16
    killall -INFO dd
    jearsh · 2010-04-22 18:38:37 5
  • Converts uppercase chars in a string to lowercase


    3
    echo StrinG | tr '[:upper:]' '[:lower:]'
    hm2k · 2010-04-22 15:09:49 5
  • run remote linux desktop

    First of all you need to run this command. X :12.0 vt12 2>&1 >/dev/null & This command will open a X session on 12th console. And it will show you blank screen. Now press Alt + Ctrl + F7. You will get your original screen. Now run given command "xterm -display :12.0 -e ssh -X user@remotesystem &". After this press Alt + Ctrl + F12. You will get a screen which will ask you for password for remote linux system. And after it you are done. You can open any window based application of remote system on your desktop. Press Alt + Ctrl + F7 for getting original screen.


    8
    xterm -display :12.0 -e ssh -X user@server &
    vishalce · 2010-04-22 10:29:24 5
  • Find MAC address of Active Eth connection


    -2
    /sbin/ifconfig|grep -B 1 inet |head -1 | awk '{print $5}'
    octopus · 2010-04-22 06:35:29 6
  • What Type of Computer Do You Have?

    Prints the type of computer you have. I think this should be used more in distros and other applications because it is so easy to get. This can also be asked by tutorials as an easy way to get your base hardware. Some alternatives: sudo dmidecode -s system-product-name and sudo smbios-sys-info-lite | sed -n 's/^Product Name: *\(.*\)/\1/p' Show Sample Output


    -2
    cat /sys/devices/virtual/dmi/id/board_name
    matthewbauer · 2010-04-22 03:21:40 9
  • Remove "#' from configuration files.


    -8
    sed -i -e 's/^#$//g' /path/to/file
    leonardovaz · 2010-04-22 02:40:22 4
  • remove comment '#' in conf files.


    -7
    grep -v ^# file.conf | grep -v ^$ > new_file.conf
    valessiobrito · 2010-04-22 02:28:34 45
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Redirect incoming traffic to SSH, from a port of your choosing
Stuck behind a restrictive firewall at work, but really jonesing to putty home to your linux box for some colossal cave? Goodness knows I was...but the firewall at work blocked all outbound connections except for ports 80 and 443. (Those were wide open for outbound connections.) So now I putty over port 443 and have my linux box redirect it to port 22 (the SSH port) before it routes it internally. So, my specific command would be: $iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 22 Note that I use -A to append this command to the end of the chain. You could replace that with -I to insert it at the beginning (or at a specific rulenum). My linux box is running slackware, with a kernel from circa 2001. Hopefully the mechanics of iptables haven't changed since then. The command is untested under any other distros or less outdated kernels. Of course, the command should be easy enough to adapt to whatever service on your linux box you're trying to reach by changing the numbers (and possibly changing tcp to udp, or whatever). Between putty and psftp, however, I'm good to go for hours of time-killing.

Send pop-up notifications on Gnome
The title is optional. Options: -t: expire time in milliseconds. -u: urgency (low, normal, critical). -i: icon path. On Debian-based systems you may need to install the 'libnotify-bin' package. Useful to advise when a wget download or a simulation ends. Example: $ wget URL ; notify-send "Done"

Block an IP address from connecting to a server
This appends (-A) a new rule to the INPUT chain, which specifies to drop all packets from a source (-s) IP address.

notify brightness level [custom]
Brightness indicator to be used in scripts that adjust brightness [especially sys that doesn't support automatically]

get all Amazon cloud (amazonws etc) ipv6 subnets

Convert epoch date to human readable date format in a log file.

Wait for file to stop changing
This loop will finish if a file hasn't changed in the last 10 seconds. . It checks the file's modification timestamp against the clock. If 10 seconds have elapsed without any change to the file, then the loop ends. . This script will give a false positive if there's a 10 second delay between updates, e.g. due to network congestion . How does it work? 'date +%s' gives the current time in seconds 'stat -c %Y' gives the file's last modification time in seconds '$(( ))' is bash's way of doing maths '[ X -lt 10 ]' tests the result is Less Than 10 otherwise sleep for 1 second and repeat . Note: Clever as this script is, inotify is smarter.

Adhoc tar backup
Creates a quick backup with tar to a remote host over ssh.

Kill all processes that listen to ports begin with 50 (50, 50x, 50xxx,...)
Run netstat as root (via sudo) to get the ID of the process listening on the desired socket. Use awk to 1) match the entry that is the listening socket, 2) matching the exact port (bounded by leading colon and end of column), 3) remove the trailing slash and process name from the last column, and finally 4) use the system(…) command to call kill to terminate the process. Two direct commands, netstat & awk, and one forked call to kill. This does kill the specific port instead of any port that starts with 50. I consider this to be safer.

see the TIME_WAIT and ESTABLISHED nums of the network
see the TIME_WAIT and ESTABLISHED nums of the network

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