Commands tagged terminal (56)

  • This command displays a clock on your terminal which updates the time every second. Press Ctrl-C to exit. A couple of variants: A little bit bigger text: watch -t -n1 "date +%T|figlet -f big" You can try other figlet fonts, too. Big sideways characters: watch -n 1 -t '/usr/games/banner -w 30 $(date +%M:%S)' This requires a particular version of banner and a 40-line terminal or you can adjust the width ("30" here). Show Sample Output


    48
    watch -t -n1 "date +%T|figlet"
    dennisw · 2009-06-21 01:02:37 35
  • I did not know this, i'd like to share...


    44
    open .
    vigo · 2009-06-10 10:55:20 24
  • If you enable multiuser, then you can permit others to share your screen session. The following conditions apply: 1. screen must be suid root; 2. "multiuser on" must be configured in ~/.screenrc; 3. control the others user(s) access with "aclchg": # ----- from ~/.screenrc-users ----- aclchg someuser +rx "#?" #enable r/o access to "someuser" aclchg someuser -x "#,at,aclchg,acladd,acldel,quit" # don't allow these aclchg otheruser +rwx "#?" # enable r/w access to "otheruser" aclchg otheruser -x "#,at,aclchg,acladd,acldel,quit" # don't allow them to use these commands # ----- After doing this (once), you start your session with: $ screen Then, the other user can join your terminal session(s) with youruserid: $ screen -r youruserid/ Note: the trailing "/" is required. Multiple users can share the same screen simultaneously, each with independent access controlled precisely with "aclchg" in the ~/.screenrc file. I use the following setup: # ~/.screenrc-base # default screenrc on any host source $HOME/.screenrc-base source $HOME/.screenrc-$HOST source $HOME/.screenrc-users # ----- Then, the base configurations are in ~/.screenrc-base; the host-specific configurations are in ~/.screenrc-$HOST, and the user configurations are in ~/.screenrc-users. The host-specific .screenrc file might contain some host-specific screen commands; e.g.: # ~/.screen-myhost # ----- screen -t 'anywhere' /bin/tcsh screen -t 'anywhere1' /bin/tcsh # ---- The .screenrc-base contains: # ~/.screenrc-base ## I find typing ^a (Control-a) awkward. So I set the escape key to CTRL-j instead of a. escape ^Jj termcapinfo xterm* ti@:te@: autodetach on zombie kr verbose on multiuser on


    38
    % screen -r someuser/
    totoro · 2009-03-25 23:59:38 11
  • 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 17
  • I've been using linux for almost a decade and only recently discovered that most terminals like putty, xterm, xfree86, vt100, etc., support hundreds of shades of colors, backgrounds and text/terminal effects. This simply prints out a ton of them, the output is pretty amazing. If you use non-x terminals all the time like I do, it can really be helpful to know how to tweak colors and terminal capabilities. Like: echo $'\33[H\33[2J'


    17
    for c in `seq 0 255`;do t=5;[[ $c -lt 108 ]]&&t=0;for i in `seq $t 5`;do echo -e "\e[0;48;$i;${c}m|| $i:$c `seq -s+0 $(($COLUMNS/2))|tr -d '[0-9]'`\e[0m";done;done
    AskApache · 2009-11-03 09:12:13 9
  • When some console full-screen program (minicom, vi, some installers) breaks down your terminal, try this command to revert all options to "sane" settings (sane is a built-in combo of a lot of stty options)


    16
    stty sane
    darkpand · 2009-11-09 15:58:06 29
  • You can convert any UNIX man page to .txt


    15
    man ls | col -b > ~/Desktop/man_ls.txt
    vigo · 2009-06-13 11:49:33 18
  • By default, screen tries to restore its old window sizes when attaching to resizable terminals. This command is the command-line equivalent to typing ^A F to fit an open screen session to the window.


    13
    screen -raAd
    rkulla · 2010-04-12 22:54:58 5

  • 12
    <ctrl+z> bg
    lucafaus · 2010-10-26 18:07:54 4
  • Use GNU/screen as a terminal emulator for anything serial console related. screen /dev/tty eg. screen /dev/ttyS0 9600 MacOSX: http://www.macosxhints.com/article.php?story=20061109133825654 Cheat Sheet: http://www.catonmat.net/blog/screen-terminal-emulator-cheat-sheet/ Show Sample Output


    11
    screen /dev/tty<device> 9600
    px · 2010-07-20 09:12:13 35
  • After typing cd directory [enter] ls [enter] so many times, I figured I'd try to make it into a function. I was surprised how smoothly I was able to integrate it into my work on the command line. Just use cdls as you would cd. It will automatically list the directory contents after you cd into the directory. To make the command always available, add it to your .bashrc file. Not quite monumental, but still pretty convenient. Show Sample Output


    8
    function cdls { cd $1; ls; }
    joem86 · 2009-03-10 19:13:47 16
  • Produces secure passwords that satisfy most rules for secure passwords and can be customized for correct output as needed. See "man pwgen" for details. Show Sample Output


    8
    pwgen --alt-phonics --capitalize 9 10
    CafeNinja · 2009-10-24 08:36:36 39
  • This is super fast and an easy way to test your terminal for 256 color support. Unlike alot of info about changing colors in the terminal, this uses the ncurses termcap/terminfo database to determine the escape codes used to generate the colors for a specific TERM. That means you can switch your terminal and then run this to check the real output. tset xterm-256color at any rate that is some super lean code! Here it is in function form to stick in your .bash_profile aa_256 () { ( x=`tput op` y=`printf %$((${COLUMNS}-6))s`; for i in {0..256}; do o=00$i; echo -e ${o:${#o}-3:3} `tput setaf $i;tput setab $i`${y// /=}$x; done ) } From my bash_profile: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output


    7
    ( x=`tput op` y=`printf %$((${COLUMNS}-6))s`;for i in {0..256};do o=00$i;echo -e ${o:${#o}-3:3} `tput setaf $i;tput setab $i`${y// /=}$x;done; )
    AskApache · 2010-09-06 10:39:27 8

  • 7
    . ~/.bashrc
    xamaco · 2012-10-13 09:07:02 9
  • Any changes to BASH shell made in .bashrc will be active in the current terminal window from the moment you execute this command, ie. aliases, prompt settings etc. No need to restart terminal. (In BASH 'source' simile to 'eval' lets you generally execute any bunch of commands stacked in a text file).


    5
    source ~/.bashrc
    knoppix5 · 2012-10-01 08:30:19 4

  • 4
    color () { local color=39; local bold=0; case $1 in green) color=32;; cyan) color=36;; blue) color=34;; gray) color=37;; darkgrey) color=30;; red) color=31;; esac; if [[ "$2" == "bold" ]]; then bold=1; fi; echo -en "\033[${bold};${color}m"; }
    zvyn · 2013-09-06 09:37:42 13
  • Simply sourcing .bashrc does not function correctly when you edit it and change an alias for a function or the other way round with the *same name*. I therefor use this function. Prior to re-sourcing .bashrc it unsets all aliases and functions.


    4
    bashrc-reload() { builtin unalias -a; builtin unset -f $(builtin declare -F | sed 's/^.*declare[[:blank:]]\+-f[[:blank:]]\+//'); . ~/.bashrc; }
    Xk2c · 2014-03-02 14:24:18 9
  • One of my favorite ways to impress newbies (and old hats) to the power of the shell, is to give them an incredibly colorful and amazing version of the top command that runs once upon login, just like running fortune on login. It's pretty sweet believe me, just add this one-liner to your ~/.bash_profile -- and of course you can set the height to be anything, from 1 line to 1000! G=$(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
  • If you launch gnome-terminal manually, you can start with three open tabs


    2
    gnome-terminal --tab --tab --tab
    0disse0 · 2009-09-03 19:36:07 3
  • This helps to keep track of what is going on when you have several tabs open in your terminal. The title automatically changes when you change directories.


    2
    export PROMPT_COMMAND='echo -ne "\033]0;${PWD/#$HOME/~}\007";'
    dstahlke · 2009-09-23 16:38:06 3
  • One of the first functions programmers learn is how to print a line. This is my 100% bash builtin function to do it, which makes it as optimal as a function can be. The COLUMNS environment variable is also set by bash (including bash resetting its value when you resize your term) so its very efficient. I like pretty-output in my shells and have experimented with several ways to output a line the width of the screen using a minimal amount of code. This is like version 9,000 lol. This function is what I use, though when using colors or other terminal features I create separate functions that call this one, since this is the lowest level type of function. It might be better named printl(), but since I use it so much it's more optimal to have the name contain less chars (both for my programming and for the internal workings). If you do use terminal escapes this will reset to default. tput sgr0 For implementation ideas, check my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output


    2
    L(){ l=`builtin printf %${2:-$COLUMNS}s` && echo -e "${l// /${1:-=}}"; }
    AskApache · 2010-06-14 04:35:30 6

  • 2
    bashrc-reload() { builtin exec bash ; }
    Xk2c · 2016-04-30 10:37:38 11
  • Continue a current job in the background and detach it from current terminal


    1
    %1 &!
    Dema · 2011-01-14 02:26:24 7
  • You may want to just use the shortcut "." instead of "source"


    1
    . ~/.bashrc
    DNSpyder · 2012-10-01 08:41:19 4
  • Changes your group to the default group, has the same effect as sourcing your profile/rc file (in any shell) or logging out and back in again.


    1
    newgrp -
    dendoes · 2012-10-01 10:23:56 6
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Replicate a directory structure dropping the files

find out how many days since given date
You can also do this for seconds, minutes, hours, etc... Can't use dates before the epoch, though.

Count number of files in subdirectories
For each directory from the current one, list the counts of files in each of these directories. Change the -maxdepth to drill down further through directories.

Adequately order the page numbers to print a booklet
Useful if you don't have at hand the ability to automatically create a booklet, but still want to. F is the number of pages to print. It *must* be a multiple of 4; append extra blank pages if needed. In evince, these are the steps to print it, adapted from https://help.gnome.org/users/evince/stable/duplex-npage.html.en : 1) Click File ▸ Print. 2) Choose the General tab. Under Range, choose Pages. Type the numbers of the pages in this order (this is what this one-liner does for you): n, 1, 2, n-1, n-2, 3, 4, n-3, n-4, 5, 6, n-5, n-6, 7, 8, n-7, n-8, 9, 10, n-9, n-10, 11, 12, n-11... ...until you have typed n-number of pages. 3) Choose the Page Setup tab. - Assuming a duplex printer: Under Layout, in the Two-side menu, select Short Edge (Flip). - If you can only print on one side, you have to print twice, one for the odd pages and one for the even pages. In the Pages per side option, select 2. In the Page ordering menu, select Left to right. 4) Click Print.

Sort files by date
Show you the list of files of current directory sorted by date youngest to oldest, remove the 'r' if you want it in the otherway.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

reverse-i-search: Search through your command line history
"What it actually shows is going to be dependent on the commands you've previously entered. When you do this, bash looks for the last command that you entered that contains the substring "ls", in my case that was "lsof ...". If the command that bash finds is what you're looking for, just hit Enter to execute it. You can also edit the command to suit your current needs before executing it (use the left and right arrow keys to move through it). If you're looking for a different command, hit Ctrl+R again to find a matching command further back in the command history. You can also continue to type a longer substring to refine the search, since searching is incremental. Note that the substring you enter is searched for throughout the command, not just at the beginning of the command." - http://www.linuxjournal.com/content/using-bash-history-more-efficiently

Get the list of local files that changed since their last upload in an S3 bucket
Can be useful to granulary flush files in a CDN after they've been changed in the S3 bucket.

print DateTimeOriginal from EXIF data for all files in folder
see output from `identify -verbose` for other keywords to filter for (e.g. date:create, exif:DateTime, EXIF:ExifOffset).

Change every instance of OLD to NEW in file FILE
Very quick way to change a word in a file. I use it all the time to change variable names in my PHP scripts (sed -i 's/$oldvar/$newvar/g' index.php)


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