Commands by Timothy (2)

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Setting global redirection of STDERR to STDOUT in a script
You have a script where =ALL= STDERR should be redirected to STDIN and you don't want to add "2>&1" at the end of each command... E.G.: $ ls -al /foo/bar 2>&1 Than just add this piece of code at the beginning of your script! I hope this can help someone. :)

For when GUI programs stop responding..
man xkill

Get IPv4 of eth0 for use with scripts
Simple and easy. No regex, no search and replace. Just clean, built-in tools.

KDE Mixer Master Mute/Unmute
arguably better than using the driver interface. lots of potentially cool stuff to be done w/ the dcop client.

List available upgrades from apt without upgrading the system

find out how many days since given date
You can also do this for seconds, minutes, hours, etc... Can't use dates before the epoch, though.

Create a DOS floppy image
mount with: mount -t msdos -o loop ./floppy.img /tmp/mnt

Find files of two different extensions and copy them to a directory

Convert numbers to SI notation
converts any number on the 'stdin' to SI notation. My version limits to 3 digits of precious (working with 10% resistors).

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


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