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Colorizes an access log
Puts a splash of color in your access logs. IP addresses are gray, 200 and 304 are green, all 4xx errors are red. Works well with e.g. "colorize access_log | less -R" if you want to see your colors while paging. Use as inspiration for other things you might be tailing, like syslog or vmstat Usage: $ tail -f access.log | colorize

Random unsigned integer
works at least in bash. returns integer in range 0-32767. range is not as good, but for lots of cases it's good enough.

Command Line to Get the Stock Quote via Yahoo
Retrieve the current stock price from Yahoo Finance. The output is simply the latest price (which could be delayed). If you want to look up stock for a different company, replace csco with your symbol.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Wait for file to stop changing
This loop will finish if a file hasn't changed in the last 10 seconds. . It checks the file's modification timestamp against the clock. If 10 seconds have elapsed without any change to the file, then the loop ends. . This script will give a false positive if there's a 10 second delay between updates, e.g. due to network congestion . How does it work? 'date +%s' gives the current time in seconds 'stat -c %Y' gives the file's last modification time in seconds '$(( ))' is bash's way of doing maths '[ X -lt 10 ]' tests the result is Less Than 10 otherwise sleep for 1 second and repeat . Note: Clever as this script is, inotify is smarter.

List only directories, one per line

Adding Color Escape Codes to global CC array for use by echo -e
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.

create a colorful 田 image

Binary clock


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