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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" }

Display 16 largest installed RPMs in size order, largest first
Interesting to see which packages are larger than the kernel package. Useful to understand which RPMs might be candidates to remove if drive space is restricted.

Look for English words in /dev/urandom
* to get the English dictionary: wget http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt

Massive change of file extension (bash)
Using bash parameters expansion

Echo the latest commands from commandlinefu on the console
A Quick variation to the latest commands list with the new-lines skipped. This is faster to read.

password recovery on debian
Appended to grub boot parameters ... gives shell ... password recovery

Check if x509 certificate file and rsa private key match
A x509 certificate and a rsa key file have in common a parameter called modulus, it is a very long hexadecimal number. That value is unique for each certficate / key pair. The command allows to do the check of this pair of values in a script using a great feature of bash. "

Play awesome rythmic noise using aplay
Try modifying the numbers in the "(i*(i>>8|i>>9)&46&i>>8))^(i&i>>13|i>>6)" part. Crudely stolen from http://www.xkcdb.com/9067

find geographical location of an ip address
a shorter version

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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