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create pdf files from text files or stdout.

Get decimal ascii code from character
printf treats first char after single ' as numeric equivalent

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.

Check your bash shell for vulnerability to the ShellShock exploit
If this command prints 'x' then your shell is vulnerable. Null output confirms that you are protected. Further reading: http://allanmcrae.com/2014/09/shellshock-and-arch-linux/

Show which programs are listening on TCP ports
Alternative: $ ss -tlpn

Shows space used by each directory of the root filesystem excluding mountpoints/external filesystems (and sort the output)

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

Rolling upgrades via aptitude
This has been my "sysupgrade" alias since ca. 2006, first used on Debian Sid, then Sabayon, and it still does its duty on Mint nowadays without breaking stuff.

Tracklist reaplace backspace to '-'
Requires perl 5.14 or greater

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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