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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

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

RTFM function
Same as the other rtfm's, but using the more correct xdg-open instead of $BROWSER. I can't find a way to open info only if the term exists, so it stays out of my version.

Print a horizontal line

bulk rename files with sed, one-liner
Far from my favorite, but works in sh and with an old sed that doesn't support '-E'

To print a specific line from a file
Just one character longer than the sed version ('FNR==5' versus -n 5p). On my system, without using "exit" or "q", the awk version is over four times faster on a ~900K file using the following timing comparison: $ testfile="testfile"; for cmd in "awk 'FNR==20'" "sed -n '20p'"; do echo; echo $cmd; eval "$cmd $testfile"; for i in {1..3}; do time for j in {1..100}; do eval "$cmd $testfile" >/dev/null; done; done; done Adding "exit" or "q" made the difference between awk and sed negligible and produced a four-fold improvement over the awk timing without the "exit". For long files, an exit can speed things up: $ awk 'FNR==5{print;exit}'

Direct auto-complete in bash
Direct auto-complete in bash

Add GPG key easy - oneliner
Replace KEY with GPG key. This command will load GPG key and add it to your system so you can use software from third party repos etc.

Find status of all symlinks
The symlinks command can show status of all symbolic links, including which links are dangling, which symlinks point to files on other file systems, which symlinks use ../ more than necessary, which symlinks are messy (e.g. having too many slashes or dots), etc. Other useful things it can do include removing all dangling links (-d) and converting absolute links to relative links (-c). The path given must be an absolute path (which is why I used $(pwd) in the example command).

awk using multiple field separators
You can use multiple field separators by separating them with | (=or). This may be helpful when you want to split a string by two separators for example. #echo "one=two three" | awk -F "=| " {'print $1, $3'} one three

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