Commands by danimath (1)

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

Speaking alarm clock
This ran on a ubuntu box using espeak for speaking text with the bash shell. On a mac you should use 'say'. Also you can change your alarm interval and your snooze interval which are currently 8 hours and 1 minute. I would run this via cron yet it's easier to disable if you run it as a command like this :P

Select and Edit a File in the Current Directory
This command displays a simple menu of file names in the current directory. After the user made a choice, the command invokes the default editor to edit that file. * Without the break statement, the select command will loop forever * Setting the PS3 prompt is optional * If the user types an invalid choice (such as the letter q), then the variable $f will become an empty string. * For more information, look up the bash's select command

Show which process is blocking umount (Device or resource is busy)
Instead of using force un-mounting, it's better to find the processes that currently use the relevant folder. Taken from: http://www.linuxhowtos.org/Tips%20and%20Tricks/findprocesses.htm

Destroy all disks on system simultaneously
This command will use the fdisk utility to find all block devices on your system, and overwrite them with data from the /dev/urandom non-blocking random number generator. CAUTION: This will irrevocably erase EVERY SINGLE physical block storage device visible to the fdisk utility, including plugged USB devices, RAID sets, LVM, etc.

Convert files from DOS line endings to UNIX line endings
The old dos2unix from sysutils has been deprecated on Debian systems to this tool.

list files recursively by size

prints line numbers
the sed way to print line numbers

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

Run a command as root, with a delay
$ sleep 1h ; sudo command or $ sudo sleep 1h ; sudo command won't work, because by the time the delay is up, sudo will want your password again.


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