Commands tagged script (36)

  • run 'nc yourip 5000', 'nc yourip 5001' or 'nc yourip 5002' elsewhere will produce an exact same mirror of your shell. This is handy when you want to show someone else some amazing stuff in your shell without giving them control over it.


    39
    script -qf | tee >(nc -kl 5000) >(nc -kl 5001) >(nc -kl 5002)
    clvv · 2010-10-11 07:55:30 12
  • Exit with error if script is not run in a terminal


    21
    [ -t 0 ] || exit 1
    cfajohnson · 2009-11-20 23:14:49 3
  • One person does `mkfifo foo; script -f foo' and another can supervise real-time what is being done using `cat foo'.


    19
    mkfifo foo; script -f foo
    realist · 2011-09-08 02:51:44 5
  • This is a (last resort) way to automate applications that provide no other ways for automation, it would send 'Hello world' to the currently active window. See the manpage (and the -text and -window entries) for how to send special characters and target specific windows. An example: Using xwininfo, I get the id of my XPlanet background window: alanceil@kvirasim:19:51:0:~> xwininfo xwininfo: Please select the window about which you would like information by clicking the mouse in that window. xwininfo: Window id: 0x3600001 "Xplanet 1.2.0" Absolute upper-left X: 0 (..etc..) Now I use xvkbd to tell it to close itself: xvkbd -xsendevent -window 0x3600001 -text "Q" Obviously, the best way is to put these commands in a shellscript - just make sure to include a short sleep (sleep .1 should suffice) after each xvkbd call, or some programs will become confused.


    15
    xvkbd -xsendevent -text "Hello world"
    Alanceil · 2009-03-20 18:58:05 1
  • Can be used for command line parameters too. If you have a more complicated way of entering values (validation, GUI, ...), then write a function i.e. EnterValue() that echoes the value and then you can write: param=${param:-$(EnterValue)}


    8
    param=${param:-$(read -p "Enter parameter: "; echo "$REPLY")}
    frans · 2011-09-08 20:48:31 0
  • Useful for use in other scripts for renaming, testing for extensions, etc. Show Sample Output


    6
    FILENAME=${FILE##*/};FILEPATH=${FILE%/*};NOEXT=${FILENAME%\.*};EXT=${FILE##*.}
    eduo · 2009-06-10 16:11:38 4
  • Run local scripts on remote server. "-T Disable pseudo-tty allocation"


    6
    ssh -T user@server < script.sh
    dlebauer · 2011-01-10 20:09:55 1
  • script -f /tmp/foo will place all output of the terminal, including carriage returns, to a file. This file can be tail dash-eff'ed by one or more other terminals to display the information of the main terminal. Good way to share one's screen on short notice. Note: This produces a very accurate output, but that includes depending on the size of your terminal to be the same. You can clear screens or even resize the terminal for others using this function; I use it in conjunction with the "mid" command in my list. Show Sample Output


    3
    script -f /tmp/foo; tail -f /tmp/foo
    robinsonaarond · 2011-11-22 15:16:08 2
  • A wrapper around ssh to automatically provide logging and session handling. This function runs ssh, which runs screen, which runs script. . The logs and the screen session are stored on the server. This means you can leave a session running and re-attach to it later, or from another machine. . . Requirements: * Log sessions on a remote server * Transparent - nothing extra to type * No installation - nothing to copy to the server beforehand . Features: * Function wrapper delegating to ssh - so nothing to remember - uses .ssh/config as expected - passes your command line option to ssh * Self-contained: no scripts to install on the server * Uses screen(1), so is: - detachable - re-attachable - shareable * Records session using script(1) * Configurable log file location, which may contain variables or whitespace L="$HOME" # local variable L="\$HOME" # server variable L="some space" . Limitations: * Log dir/file may not contain '~' (which would require eval on the server) . . The sessions are named by the local user connecting to the server. Therefore if you detach and re-run the same command you will reconnect to your original session. If you want to connect/share another's session simply run: USER=bob ssh root@server . The command above is stripped down to an absolute minimum. A fully expanded and annotated version is available as a Gist (git pastebin): https://gist.github.com/flatcap/3c42326abeb1197ee714 . If you want to add timing info to script, change the command to: ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script --timing=\"$L-timing\" -f \"$L\"";} Show Sample Output


    3
    ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script -f \"$L\"";}
    flatcap · 2015-10-14 13:14:29 1

  • 3
    sudo timedatectl set-timezone $(curl -s worldtimeapi.org/api/ip.txt | sed -n 's/^timezone: //p')
    fumok · 2019-03-12 16:04:11 0
  • In order to write bash-scripts, I often do the task manually to see how it works. I type ### at the start of my session. The function fetches the commands from the last occurrence of '###', excluding the function call. You could prefix this with a here-document to have a proper script-header. Delete some lines, add a few variables and a loop, and you're ready to go. This function could probably be much shorter...


    2
    quickscript () { filename="$1"; history | cut -c 8- | sed -e '/^###/{h;d};H;$!d;x' | sed '$d' > ${filename:?No filename given} }
    joedhon · 2014-02-09 12:19:29 0
  • Often I need to edit a bash or perl script I've written. I know it's in my path but I don't feel like typing the whole path (or I don't remember the path).


    1
    vim `which <scriptname>`
    bunedoggle · 2009-05-08 17:21:47 2
  • Better solution in case of many clients, imo. Show Sample Output


    1
    script -qf >(nc -ub 192.168.1.255 5000)
    Archiater · 2011-04-23 12:38:25 0
  • Uses history to get the last n+1 commands (since this command will appear as the most recent), then strips out the line number and this command using sed, and appends the commands to a file.


    1
    history | tail -(n+1) | head -(n) | sed 's/^[0-9 ]\{7\}//' >> ~/script.sh
    unixmonkey15842 · 2011-06-08 13:40:58 0
  • A quick alias I use right before logging into a server so that I have a log of the transactions as well as the ability to re-connect from another computer. Useful for when your boss says "what commands did you run again on that server?" and you had already closed the terminal ;) I wrapped it in a script now, with more features, but this is the heart of it. Never leave home without it.


    1
    alias m='screen -S $$ -m script'
    robinsonaarond · 2015-10-01 18:07:18 1
  • Create a bash script to change the modification time for each file in 'files.txt' such that they are in the same order as in 'files.txt' File name for bash script specified by variable, 'scriptName'. It is made an executable once writing into it has been completed. Show Sample Output


    1
    scriptName="reorder_files.sh"; echo -e '#!/bin/sh\n' > "${scriptName}"; cat files.txt | while read file; do echo "touch ${file}; sleep 0.5;" >> "${scriptName}"; done; chmod +x "${scriptName}";
    programmer · 2016-04-19 11:52:00 3
  • 1. it find your public ip via ifconfig.io 2. than use this IP to request your timezone via worldtimeapi.org 3. and send it to the command timedatectl set-timezone


    1
    sudo timedatectl set-timezone $(curl -s worldtimeapi.org/api/ip.txt | sed -n 's/^timezone: //p')
    jodumont · 2019-03-09 21:52:32 3
  • If your script needs to be run in a terminal, this line at the top will stop it running if you absent-mindedly double-click the icon, perhaps intending to edit it. (Of course this won't help with scripts that run in the background.)


    0
    tty > /dev/null 2>&1 || { aplay error.wav ; exit 1 ;}
    johnraff · 2009-11-04 16:18:00 3
  • This command will play back each keystroke in a session log recorded using the script command. You'll need to replace the ^[ ^G and ^M characters with CTRL-[, CTRL-G and CTRL-M. To do this you need to press CTRL-V CTRL-[ or CTRL-V CTRL-G or CTRL-V CTRL-M. You can adjust the playback typing speed by modifying the sleep. If you're not bothered about seeing each keypress then you could just use: cat session.log Show Sample Output


    0
    (IFS=; sed 's/^[]0;[^^G]*^G/^M/g' <SessionLog> | while read -n 1 ITEM; do [ "$ITEM" = "^M" ] && ITEM=$'\n'; echo -ne "$ITEM"; sleep 0.05; done; echo)
    jgc · 2010-01-20 16:11:32 2
  • As a user, deletes all your posts from a MyBB board (provided you have the search page listings of all your posts saved into the same directory this command is run from). Full command: for i in *; do cat $i | grep pid | sed -e 's/;/\ /g' -e 's/#/\ /g' -e 's/pid=/\ /g' | awk -F ' ' '{print $2}' >> posts.txt; done; for c in `cat posts.txt`; do curl --cookie name= --data-urlencode name=my_post_key=\&delete=1\&submit=Delete+Now\&action=deletepost\&pid=$c --user-agent Firefox\ 3.5 --url http://url/editpost.php?my_post_key=\&delete=1\&submit=Delete+Now\&action=deletepost\&pid=$c; sleep 2s; done; echo


    0
    curl --cookie name=<cookie_value> --data-urlencode name=my_post_key=<post_key>\&delete=1\&submit=Delete+Now\&action=deletepost\&pid=$c --user-agent Firefox\ 3.5 --url http://url/editpost.php?my_post_key=<post_key>\&delete=1\&submit=Delete+Now\&action=dele
    mrlockfs · 2010-07-14 01:50:48 0
  • You define your variable MYVAR with the desired search pattern: MYVAR= ...which can then be searched with the find command. This is useful if you in a script, where you want the arguments to be fed into the find command. The provided search is case insensitive (-iname) and will find all files and directories with the pattern MYVAR (not exact matches). This may go without saying, but if you want exact matches remove the \* and if you want case sensitive, use the -name argument.


    0
    find . -iname \*${MYVAR}\* -print
    Buzzcp · 2010-08-04 05:43:51 0
  • This works fine too.


    0
    find "$1" -iname "*$2*"
    dbbolton · 2010-08-04 11:10:42 0
  • I submitted a command like this without $0 if $BASH_SOURCE is unset. Therefor, it did only work when using ./script, not using 'sh script'. This version handles both, and will set $mydir in a script to the current working directory. It also works on linux, osx and probably bsd.


    0
    mydir=$(cd $(dirname ${BASH_SOURCE:-$0});pwd)
    xeor · 2011-04-27 16:33:38 0
  • Crash Override, man! Apparently the exec call tricks BASH into setting the output buffer size to 0 under the assumption that the system (or the calling shell) will handle the output buffering. trapping the ERR signal will stop the subshell from dying and sending the ERR signal to the main script--which will terminate immediately if it does--when the program fails. The only problem is that the kernel will output a whole bunch of stack trace garbage directly to the console device once the process segfaults, so there's no way to prevent it from being output [that I know of].


    0
    (trap 'true' ERR; exec <SEGFAULT_PRONE_PROGRAM>)
    h3xx · 2011-07-25 02:30:52 0
  • If Argument $1 is supplied, assign it to variable. Otherwise continue on.


    0
    [ $1 ] && my_dir=$1
    robinsonaarond · 2011-11-30 15:02:20 0
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Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Type strait into a file from the terminal.
Takes input from the connected terminal and dumps it to the specified file. Stop writing and close file with control + D or the end of line character. Useful for copying+pasting large blobs of text over SSH to a new machine.

DVD ripping with ffmpeg
To rip DVD movie to ogg format using ffmpeg, follow these steps. 1) find the vob files on the mounted video DVD in VIDEO_TS that stores the movie itself. There would be a few other VOB files that stores splash screen or special features, the vob files for the movie itself can be identified by its superior size. You can verify these vob files by playing them directly with a player (e.g. mplayer) 2) concatenate all such vob files, pipe to ffmpeg 3) calculate the video size and crop size. The ogg video size must be multiple of 16 on both width and height, this is inherit limitation of theora codec. In my case I took 512x384. The -vcodec parameter is necessary because ffmpeg doesn't support theora by itself. -acodec is necessary otherwise ffmpeg uses flac by default.

Find brute force attempts on SSHd
Searches the /var/log/secure log file for Failed and/or invalid user log in attempts.

A nice way to show git commit history, with easy to read revision numbers instead of the default hash

Find inside files two different patterns in the same line and for matched files show number of matched lines
The option -print0 for find and -0 for grep help prevent issue with weird characters or spaces in filenames. Furthermore with xargs there is no limited number of arguments that find can throw.

Get list of servers with a specific port open
Change the -p argument for the port number. See "man nmap" for different ways to specify address ranges.

detach remote console for long running operations
Starts midnightcommander and allows you to detach the console; use ctrl-\ to detach Then at a later time you can reconnect using $ dtach -a /tmp/wires-mc In my experience dtach works much better for programs like irssi, mutt, mc, aptitude than screen does.

a find and replace within text-based files
using find's exec option instead of a for loop and using sed's -i option for inplace replacement. no need to do the file swap.

Using numsum to sum a column of numbers.
numsum is part of of the num-utils package, which is available in some Linux distros and can also be downloaded at http://suso.suso.org/xulu/Num-utils. It contains about 10 different programs for dealing with numbers from the command line. Obviously you can do a lot of things that the num-utils programs do in awk, sed, bash, perl scripts, but num-utils are there so that you don't have to remember the syntax for more complex operations and can just think: compute the sum, average, boundary numbers, etc.


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