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Create passwords and store safely with gpg
Adjust the $ head -c part for password length. I use filenames like "hans@commandlinefu.com.gpg" and a vim which automatically decrypts files with .gpg suffixes.

Change SSH RSA passphrase
Protects your secret identity with a passphrase. OSX 10.6 automatically does key forwarding and can store the passphrase in the keychain. For other OSes, use ssh -A or set ForwardAgent in ssh_config to enable forwarding. Then use ssh-agent/ssh-add.

print all except first collumn

Script Terminal Session
script -f /tmp/foo will place all output of the terminal, including carriage returns, to a file. This file can be tail dash-eff'ed by one or more other terminals to display the information of the main terminal. Good way to share one's screen on short notice. Note: This produces a very accurate output, but that includes depending on the size of your terminal to be the same. You can clear screens or even resize the terminal for others using this function; I use it in conjunction with the "mid" command in my list.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Generate a list of installed packages on Debian-based systems
This command is useful when you want to install the same packages on another fresh OS install for example. To do that, use: $ sudo dpkg --set-selections < LIST_FILE

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

find file/dir by excluding some unwanted dirs and filesystems
Consider using this cmd when: 1. You are planning to traverse a big directory. 2. There is a subdir you don't want find to decend to. (entirely ignore) 3. You don't want find to decend to any mounted filesystems under this dir. * The -xdev flag tells find do not go to other filesystems. * -path ./junk_dir -prune is the pattern to ignore ./junk_dir entirely. * The rest is the typical search and print. To ignore multiple subdirs, you can just iterate the pattern, e.g. find . -path ./junk1 -prune -o -path ./junk2 -prune ... If you do want to include other filesystems, then remove -xdev flag. If you want to search files, then change -type d to -type f.

Update zone file Serial numbers
Will edit *.db files in the same directory with todays date. Useful for doing a mass update to domains on a nameserver, adding spf records, etc. Looks for a string starting with 200 or 201 followed by 7 numbers, and replaces with todays date. This won't overwrite Ip's but i would still do some double checking after running this. Make sure your server's date is correct, otherwise insert your own serial number. $rndc reload should usually follow this command.

List only hidden files
You can omit the -d to see what's inside directories. In that case, you may want -a to see dotfiles inside those directories. (Otherwise you don't need -a since you're explicitly looking at them.)


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