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I like the other three versions but one uses nested loops and another prints every color on a separate line. Both versions fail to reset colors before giving the prompt back.
This version uses the column command to print a table so all the colors fit on one screen. It also resets colors back to normal before as a last step.
Re-formatting for command #5879. The table is a little wonky, the colors are period 36, but of course that's not a divisor of 256.
Same as http://www.commandlinefu.com/commands/view/5876, but for bash.
This will show a numerical value for each of the 256 colors in bash. Everything in the command is a bash builtin, so it should run on any platform where bash is installed. Prints one color per line. If someone is interested in formatting the output, paste the alternative.
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
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
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
A bit different from some of the other submissions. Has bold and uses all c printable characters. Change the bs=value to speed up and increase the sizes of the bold and non-bold strings.
blue and yellow colored bash prompt for a Hanukkah celebration on your box
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 $'\33[H\33[2J'
Removes ANSI color and end of line codes to the [{attr1};...;{attrn}m format.
Same as the cool matrix style command ( http://www.commandlinefu.com/commands/view/3652/matrix-style ), except replacing the printed character with randomness. The command mentioned is much faster and thus more true to the matrix. However, mine can be optimized, but I wasted ... i mean spent enough time on it already
I like the fact the Patola's version uses only ones and zeros, but I also like the sparse output of the other versions. This one combines both of those features and eliminates some unnecessary cruft.
You can vary the sparseness by changing "$(($RANDOM % 5))" to another number. The number in this term "$(($RANDOM % 4))" controls how frequently the numbers are output bold.
I was looking for the fastest way to create a bunch of ansi escapes for use in echo -e commands throughout a lot of my shell scripts. This is what I came up with, and I actually stick that loop command in a function and then just call that at the beginning of my scripts to not clutter the environment with these escape codes, which can wreck havok on my terminal when I'm dumping the environment. More of a cool way to store escape ansi codes in an array. You can echo them like:
echo -e "${CC[15]}This text is black on bright green background."
I usually just use with a function:
# setup_colors - Adds colors to array CC for global use
# 30 - Black, 31 - Red, 32 - Green, 33 - Yellow, 34 - Blue, 35 - Magenta, 36 - Blue/Green, 37 - White, 30/42 - Black on Green '30\;42'
function setup_colors(){ declare -ax CC; for i in `seq 0 7`;do ii=$(($i+7));CC[$i]="\033[1;3${i}m";CC[$ii]="\033[0;3${i}m";done;CC[15]="\033[30;42m"; export R='\033[0;00m';export X="\033[1;37m"; };
export -f setup_colors
CC[15] has a background of bright green which is why it is separate. R resets everything, and X is my default font of bright white.
CC[15]="\033[30;42m"; R=$'\033[0;00m'; X=$'\033[1;37m'
Those are just my favorite colors that I often use in my scripts. You can test which colors by running
for i in $(seq 0 $((${#CC[@]} - 1))); do echo -e "${CC[$i]}[$i]\n$R"; done
See: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html for more usage.
This will diff your local version of the file with the latest version in svn. I put this in a shell function like so:
svd() { vimdiff <(svn cat "$1") "$1"; }
It's the same command as submitted, but first with a command to make all characters green. It's the only way it looked "matrix-like" on my gnome-terminal.
This will create a permanent alias to colorize the search pattern in your grep output