Commands using echo (1,545)

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Read a keypress without echoing it
This shell snippet reads a single keypress from stdin and stores it in the $KEY variable. You do NOT have to press the enter key! The key is NOT echoed to stdout! This is useful for implementing simple text menus in scripts and similar things.

How to know the total number of packages available

Using commandoutput as a file descriptor
Description is moved to "Sample output" because the html sanitizer for commandlinefu breaks the examples..

Releases Firefox of a still running message
Sometimes Firefox crashes or is bad finished and the message the process is still running appear while it's not. This also works when you sharing account from a NIS server and try to open the browser on multiple computers.

Batch resize all images in the current directory that are bigger than 800px, height or weight.
You need to install imagemagick. On Debian type: # apt-get install imagemagick

Add a Clock to Your CLI

runs a X session within your X session
http://www.debian-administration.org/article/Running_multiple_X11_sessions

Create QR codes from a URL.
QR codes are those funny square 2d bar codes that everyone seems to be pointing their smart phones at. Try the following... $ qrurl http://xkcd.com Then open qr.*.png in your favorite image viewer. Point your the bar code reader on your smart phone at the code, and you'll shortly be reading xkcd on your phone. URLs are not the only thing that can be encoded by QR codes... short texts (to around 2K) can be encoded this way, although this function doesn't do any URL encoding, so unless you want to do that by hand it won't be useful for that.

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

Convert all files for iPhone with HandbrakeCLI


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