Commands by ghthor (1)

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Turning off display
To turn off monitor: xset dpms force off To turn on, simply press a key, or move mouse/mousepad.

I finally found out how to use notify-send with at or cron
The simplest way to do it. Works for me, at least. (Why are the variables being set?)

download and unpack tarball without leaving it sitting on your hard drive

directly ssh to host B that is only accessible through host A
Of course you need to be able to access host A for this ;-)

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

Remove trailing space in vi

Function to output an ASCII character given its decimal equivalent

cooking a list of numbers for calculation
When you've got a list of numbers each on its row, the ECHO command puts them on a simple line, separated by space. You can then substitute the spaces with an operator. Finally, pipe it to the BC program.

kill some process (same as others) but parsing to a variable
Kills a process matching program. I suggest using $ pgrep -fl program to avoid over-killings Nice the following: kills all bash process owned by guest $ pkill -9 -f bash -u guest

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }


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