Commands using write (21)

  • This command creates and burns a gapless audio CD with 99 tracks. Each track is a 30 second sine wave, the first is 1 Hz, the second 2 Hz, and so on, up to 99 Hz. This is useful for testing audio systems (how low can your bass go?) and for creating the constant vibrations needed to make non-Newtonian fluids (like cornstarch and water) crawl around. Note, this temporarily creates 500MB of .cdda files in the current directory. If you don't use the "rm" at the end of the command, you can burn more disks using cdrdao write cdrdao.toc Prerequisites: a blank CD-R in /dev/cdrw, sox (http://sox.sourceforge.net/), and cdrdao (http://cdrdao.sourceforge.net/). I'm also assuming a recent version of bash for the brace expansion (which just looks nicer than using seq(1), but isn't necessary). Show Sample Output


    24
    (echo CD_DA; for f in {01..99}; do echo "$f Hz">&2; sox -nt cdda -r44100 -c2 $f.cdda synth 30 sine $f; echo TRACK AUDIO; echo FILE \"$f.cdda\" 0; done) > cdrdao.toc && cdrdao write cdrdao.toc && rm ??.cdda cdrdao.toc
    hackerb9 · 2009-11-17 06:23:42 12
  • Depending on the TERM, the terminfo version, ncurses version, etc.. you may be using a varied assortment of terminal escape codes. With this command you can easily find out exactly what is going on.. This is terminal escape zen! ( 2>&2 strace -f -F -e write -s 1000 sh -c 'echo -e "initc\nis2\ncnorm\nrmso\nsgr0" | tput -S' 2>&1 ) | grep -o '"\\[^"]*"' --color=always "\33]4;%p1%d;rgb:%p2%{255}%*%{1000}%/%2.2X/%p3%{255}%*%{1000}%/%2.2X/%p4%{255}%*%{1000}%/%2.2X\33\\\33[!p\33[?3;4l\33[4l\33>\33[?12l\33[?25h\33[27m\33(B\33[m" Lets say you want to find out what you need to echo in order to get the text to blink.. echo -e "`tput blink`This will blink`tput sgr0` This wont" Now you can use this function instead of calling tput (tput is much smarter for portable code because it works differently depending on the current TERM, and tput -T anyterm works too.) to turn that echo into a much faster executing code. tput queries files, opens files, etc.. but echo is very strait and narrow. So now you can do this: echo -e "\33[5mThis will blink\33(B\33[m This wont" More at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output


    3
    termtrace(){( strace -s 1000 -e write tput $@ 2>&2 2>&1 ) | grep -o '"[^"]*"';}
    AskApache · 2010-03-17 08:53:41 7
  • Hides all Files and Folders on the MacOS Desktop. To show files and folders, type "true" instead of "false". "Finder" at the end is case sensitive, "finder" doesn’t work


    2
    defaults write com.apple.finder CreateDesktop -bool false;killall Finder
    vranx · 2019-10-18 12:13:56 111
  • In Mac OS X, pressing Command+H will hide an application. While that application's windows vanish, there is no other visual feedback, meaning there is no immediate distinction between an application running with no windows open and a hidden application. This command turns hidden applications' icons transparent, providing a clear and obvious distinction. Change YES to NO to restore the previous functionality.


    1
    defaults write com.apple.Dock showhidden -bool YES
    Vulpine · 2009-02-15 22:13:35 7
  • Mac OS X 10.5 (Leopard) introduced a new, 3D, reflective Dock. For those of us who prefer the Dock to be a little less distracting, this command is the answer. The Dock will be rendered in the same style as when pinned to the left- or right-hand side of the screen. Replace YES with NO to restore the 3D Dock.


    1
    defaults write com.apple.Dock no-glass -boolean YES; killall Dock
    Vulpine · 2009-02-17 23:01:58 8
  • Dashboard is OS X utility application. When you hit F12, Dashboard springs forward, dimming the background, some people have claimed memory or performance problems. In my case, I just don't use it, there may be other reasons you?d rather not have Dashboard available. Change YES to NO to restore the previous functionality.


    0
    defaults write com.apple.dashboard mcx-disabled -boolean YES; killall Dock
    starchox · 2009-02-17 23:22:24 7

  • 0
    write user anytext
    mahendra · 2009-02-27 18:58:36 9
  • Swap TRUE with FALSE to turn it off again. Note: Finder must be relaunched afterwards to see the effect. For example like this: killall Finder && open /System/Library/CoreServices/Finder.app


    0
    defaults write com.apple.Finder AppleShowAllFiles TRUE
    Svish · 2009-03-09 13:55:31 5
  • This command will use the short username (ie: bsmith) instead of the full (or long) name (ie: Bob Smith), by default in the network authentication dialog, ie: when connecting to servers. Resulting in one less step/time saved. Simply change the boolean value to "NO" (ie: "... -bool NO") to revert to the system's default behavior.


    0
    defaults write /Library/Preferences/com.apple.NetworkAuthorization UseShortName -bool YES
    offworlder · 2009-12-01 05:39:36 3
  • Enables widgets to be placed onto the desktop. Click and hold the widget and press F12 to drag it onto the desktop. Repeat the process again to drag a widget back onto the dashboard. You may need to log off or restart for it to take effect.


    0
    defaults write com.apple.dashboard devmode YES
    rpavlick · 2010-03-30 22:50:27 3
  • Change the file location in the second half of the string to the exact file location of your chosen picture.


    0
    defaults write /Library/Preferences/com.apple.loginwindow DesktopPicture "/System/Library/CoreServices/Finder.app/Contents/Resources/vortex.png"
    rpavlick · 2010-03-30 22:52:19 4

  • 0
    defaults write com.apple.desktopservices DSDontWriteNetworkStores true
    rpavlick · 2010-10-06 13:19:41 3
  • Insert an additional (moveable) spacer on the left side of the Dock in Mac OS X


    0
    defaults write com.apple.dock persistent-apps -array-add '{tile-data={}; tile-type="spacer-tile";}'; killall Dock
    ratonovitch · 2011-07-26 02:03:29 5
  • Insert an additional (moveable) spacer on the right side of the Dock in Mac OS X


    0
    defaults write com.apple.dock persistent-others -array-add '{tile-data={}; tile-type="spacer-tile";}'; killall Dock
    ratonovitch · 2011-07-26 02:05:17 3
  • In Mac OS X, by default, you have to click the mouse on a Terminal window before you can type in it. You can change this behavior to mimic the X11 behavior of focusing on the window on mouseover.


    0
    defaults write com.apple.terminal FocusFollowsMouse -string YES
    ratonovitch · 2011-07-26 02:15:04 3

  • 0
    defaults write com.apple.finder AppleShowAllFiles TRUE
    JimFriend · 2014-05-17 22:00:23 8
  • Pressing a key will now repeat normally, instead of bringing up the accent/more options menu.


    0
    defaults write -g ApplePressAndHoldEnabled -bool false
    JimFriend · 2014-06-06 17:46:36 8
  • pts/33 is variable you can do before you send message to on which pts the user is following ssh youraccount@192.168.1.168 who


    0
    ssh youraccount@192.168.1.168 write toUsername pts/33
    aysadk · 2017-07-27 10:25:38 21
  • In Mac OS 9, the "New Folder" keyboard shortcut was Command+N, but in Mac OS X this was changed to "New Finder Window" instead, with "New Folder" taking the more awkward shortcut of Command+Shift+N. This command reverses their mappings.


    -1
    defaults write com.apple.finder NSUserKeyEquivalents -dict 'New Finder Window' '@$N' 'New Folder' '@N'; killall Finder
    Vulpine · 2009-02-17 23:20:53 7
  • When you press "cmd+n" in TextMate, you can have "HTML" language as default document format... You can also define other languages too. You need to know the UUID of your language bundle.


    -1
    defaults write com.macromates.textmate OakDefaultLanguage 17994EC8-6B1D-11D9-AC3A-000D93589AF6
    vigo · 2009-10-20 07:10:34 4
  • Starts a bunch of background jobs to write random garbage to everyone else's terminals. The "\n" in IFS should be an actual newline, but I can't put that in the command. Show Sample Output


    -1
    tmpIFS=IFS; IFS='\n'; users=`who | awk '{print $1}'`; for u in users; do; write $u < /dev/urandom &; done; IFS=tmpIFS
    tbodt · 2014-02-12 23:36:40 8

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Display duplicated lines in a file
Displays the duplicated lines in a file and their occuring frequency.

type partial command, kill this command, check something you forgot, yank the command, resume typing.
Example : $ vim /etc/fstab ## damn $ $ sudo ## like a boss. Example 2 : $ sudo vim /root/bin/ ##uh... autocomplete doesn't work... $ $ sudo ls /root/bin ##ah! that's the name of the file! $ sudo vim /root/bin/ ##resume here! Thanks readline!

Always tail/edit/grep the latest file in a directory of timestamped files
zsh only If you have this command in your history, you can always re-run it and have it reference the latest file. The glob matches all timestamped files and then the resulting array is sorted by modification time (m) and then the first element in the sorted array is chosen (the latest)

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

List of macros defined by gcc
Lists all macros and their values defined by gcc.

Create A Continuous Yahoo! News Ticker For The Terminal
This creates a permanent stock ticker in the terminal. it has scrolling action and refreshes when each cycle is done to get the latest news.

Using numsum to sum a column of numbers.
if you, like me, do not have the numsum, this way can do the same.

Preserve user variables when running commands with sudo.
In this case the current user has proxy variable set which allows access to the rpm on the internet but needs root privs to install it. Running sudo -E preserves the current user proxy var and allows the rpm install to be executed with sudo.

return external ip
curl inet-ip.info -> 113.33.232.62\n curl inet-ip.info/ip -> 113.33.232.62 curl inet-ip.info/json -> JSON print curl inet-ip.info/json/indent -> JSON pretty print curl inet-ip.info/yaml -> YAML format curl inet-ip.info/toml -> TOML format http://inet-ip.info

Show total size of each subdirectory, broken down by KB,MB,GB,TB


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