Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files. Show Sample Output
Pure Bash
This will print a row of characters the width of the screen without using any external executables. In some cases, COLUMNS may not be set. Here is an alternative that uses tput to generate a default if that's the case. And it still avoids using tr.
printf -v row "%${COLUMNS:-$(tput cols)}s"; echo ${row// /#}
The only disadvantage to either one is that they create a variable.
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Useful if you have a list of images called 1 2 3 4 and so on, you can adapt it to rewrite it as 4 (in this example) 0-padded number. Show Sample Output
usage: mem memcache-command [arguments] where memcache-command might be: set add get[s] append prepend replace delete incr decr cas stats verbosity version notes: exptime argument is set to 0 (no expire) flags argument is set to 1 (arbitrary)
Automatically drops mount points that have non-numeric sizes (e.g. /proc). Tested in bash on Linux and AIX. Show Sample Output
A bitcoin "brainwallet" is a secret passphrase you carry in your brain. The Bitcoin Brainwallet Exponent Calculator is one of three functions needed to calculate the bitcoin PRIVATE key. Roughly, the formula is exponent = sha256 (passphrase) Note that this is a bash function, which means you have to type its name to invoke it. You can check the accuracy of the results here http://brainwallet.org Show Sample Output
Outputs utf-8 smileys Show Sample Output
Old snapshots can cause problems. It's best to remove them when finished. I use this script to remove all snapshots. The "while read" command is necessary because my vm names contain spaces. The "time" command reports how long the process runs.
I use this as an alias: alias authplain "printf '\!:1\0\!:1\0\!:2' | mmencode | tr -d '\n' | sed 's/^/AUTH PLAIN /'" then.. # authplain someuser@somedomain.com secretpassword AUTH PLAIN c29tZXVzZXJAc29tZWRvbWFpbi5jb20Ac29tZXVzZXJAc29tZWRvbWFpbi5jb20Ac2VjcmV0cGFzc3dvcmQ= # Show Sample Output
Replace 70 with the desired height. Replace 180 with the desired width. I put it in my bashrc, because by default my terminal is too small.
this command prints itself out. it doesn't need to be stored in a file and it isn't as easy as
echo $BASH_COMMAND
for information on quines see http://en.wikipedia.org/wiki/Quine_(computing)
This will show the amount of physical RAM that is left unused by the system. Show Sample Output
Should be a bit more portable since echo -e/n and date's -Ins are not. Show Sample Output
Prints 0's and 1's in The Matrix style. You can easily modify to print 0-9 digits using $RANDOM %10 insted of %2.
Unlike other methods that use pipes and exec software like tr or sed or subshells, this is an extremely fast way to print a line and will always be able to detect the terminal width or else defaults to 80. It uses bash builtins for printf and echo and works with printf that supports the non-POSIX `-v` option to store result to var instead of printing to stdout.
Here it is in a function that lets you change the line character to use and the length with args, it also supports color escape sequences with the echo -e option.
function L() { local l=; builtin printf -vl "%${2:-${COLUMNS:-`tput cols 2>&-||echo 80`}}s\n" && echo -e "${l// /${1:-=}}"; }
With color:
L "`tput setaf 3`="
1. Use printf to store n space chars followed by a newline to an environment variable "l" where n is local environment variable from $COLUMNS if set, else it will use `tput cols` and if that fails it will default to 80.
2. If printf succeeds then echo `$l` that contains the chars, replacing all blank spaces with "-" (can be changed to anything you want).
From: http://www.askapache.com/linux/bash_profile-functions-advanced-shell.html http://www.askapache.com/linux/bash-power-prompt.html
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Replace the underscore with any other character. e.g. + or - or =
Displays six rows and five columns of random numbers between 0 and 1. If you need only one column, you can dispense with the "for" loop. Show Sample Output
it is not work with Cygwin's bash3.X. Test in Linux. use printf "%'f" number while it is floating point number Show Sample Output
Using column to format a directory listing Show Sample Output
Works on real time clock, unix time based, decrementing the actual time from initial time saved in an environment variable exported to child process inside watch Shows elapsed time from start of script in hh:mm:ss format Non afected by system slow down due to the use of date.
My version uses printf and command substitution ($()) instead of echo -e and xargs, this is a few less chars, but not real substantive difference. Also supports lowercase hex letters and a backslash (\) will make it through unescaped Show Sample Output
A cronjob command line to email someone when a webpages homepage is updated.
displays current time in "binary clock" format (loosely) inspired by: http://www.thinkgeek.com/homeoffice/lights/59e0/ "Decoding": 8421 .... - 1st hour digit: 0 *..* - 2nd hour digit: 9 (8+1) .*.. - 1st minutes digit: 4 *..* - 2nd minutes digit: 9 (8+1) Prompt-command version: PROMPT_COMMAND='echo "10 i 2 o $(date +"%H%M"|cut -b 1,2,3,4 --output-delimiter=" ") f"|dc|tac|xargs printf "%04d\n"|tr "01" ".*"' Show Sample Output
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