Commands using echo (1,545)

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ping as traceroute
This command uses ping to get the routers' IP addresses to the destination host as traceroute does. If you know what I mean..

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

Create a random password encrypted with md5 with custom lenght
This was useful to generate random passwords to some webpage users, using the sample code, inside a bash script

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

Mac Sleep Timer
Schedule your Mac to sleep at any future time. Also wake, poweron, shutdown, wakeorpoweron. Or repeating with $ sudo pmset repeat wakeorpoweron MTWRFSU 7:00:00 Query with $ pmset -g sched Lots more at http://www.macenterprise.org/articles/powermanagementandschedulingviathecommandline

macOS: Save disk space by moving apps to external drives
Because Mac app bundles contain everything in one place, it makes running them from anywhere, including from a device such as a USB flash drive or external HDD, possible. So if your Mac has a mere 256GB of storage (as mine does), you can free up large quantities of disk space by storing apps like, say, Xcode on external devices.

Getting Screen's Copy Buffer Into X's Copy Buffer (on Linux)
This command will let you just type c-a b (which means press 'ctrl' then 'a' then 'b'), and screen will save your copy buffer to /tmp/screen-exchange, and then execute xsel to copy the contents of that file into the system's X clipboard. 1. Install Conrad Parker's xsel from http://www.vergenet.net/~conrad/software/xsel/ 2. Add these lines to your .screenrc # Add cool line to make copying to x clipboard possible. # This binds C-a b to copy screen's copy buffer to the system clipboard. bind b eval writebuf 'exec /bin/sh -c "xsel -i -b < /tmp/screen-exchange"' 'exec /bin/sh -c "killall xsel"' 3. Restart screen. 4. Test it by typing c-a [ to enter copy mode. 5. Select some text using vi movement keys (h, j, k, l, etc...) and starting your selection by hitting the space bar, moving with vi movement keys, and then ending your selection with the space bar. 6. Type C-a b, and screen will use xsel to copy your screen copy buffer to the system's X clipboard buffer. 7. Then you can paste the screen copy buffer into any X program. Note: If you're using Mac OSX, you can use pbcopy instead of xsel. Also Note: The second exec in the .screenrc file, which runs killall on xsel, is necessary, because even when you redirect a file to xsel, xsel waits for you to press ctrl-c to kill it, and have it stop waiting for more input. Since xsel forces screen to wait, and I don't want to press ctrl-c, I send the equivalent of ctrl-c with killall causing xsel to write /tmp/screen-exchange to the X clipboard, and then exit. It's a hack, but it works. If you know how to get this to work without a lame hack leave a comment explaining how.

Remove all unused kernels with apt-get
Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel). I'm bummed that this took 228 characters. I'd like to see a simpler version.

currently mounted filesystems in nice layout
Particularly useful if you're mounting different drives, using the following command will allow you to see all the filesystems currently mounted on your computer and their respective specs with the added benefit of nice formatting.

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


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