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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
Download google video with wget. Or, if you wish, pass video URL to ie mplayer to view as stream.
1. VURL: replace with url. I.e. http://video.google.com/videoplay?docid=12312312312312313#
2. OUPUT_FILE : optionally change to a more suited name. This is the downloaded file. I.e. foo.flv
# Improvements greatly appreciated. (close to my first linux command after ls -A :) )
Breakedown pipe by pipe:
1. wget: html from google, pass to stdout
2. grep: get the video url until thumbnailUrl (not needed)
3. grep: Strip off everything before http://
4. sed: urldecode
5. echo: hex escapes
6. sed: stipr of tailing before thumbnailUrl
7. wget: download. Here one could use i.e. mplayer or other...
One of my favorite ways to impress newbies (and old hats) to the power of the shell, is to give them an incredibly colorful and amazing version of the top command that runs once upon login, just like running fortune on login. It's pretty sweet believe me, just add this one-liner to your ~/.bash_profile -- and of course you can set the height to be anything, from 1 line to 1000!
$ G=$(stty -g);stty rows $((${LINES:-50}/2));top -n1; stty $G;unset G
Doesn't take more than the below toprc file I've added below, and you get all 4 top windows showing output at the same time.. each with a different color scheme, and each showing different info. Each window would normally take up 1/4th of your screen when run like that - TOP is designed as a full screen program. But here's where you might learn something new today on this great site.. By using the stty command to change the terminals internal understanding of the size of your terminal window, you force top to also think that way as well.
# save the correct settings to G var.
$ G=$(stty -g)
# change the number of rows to half the actual amount, or 50 otherwise
$ stty rows $((${LINES:-50}/2))
# run top non-interactively for 1 second, the output stays on the screen (half at least)
$ top -n1
# reset the terminal back to the correct values, and clean up after yourself
$ stty $G;unset G
This trick from my [ http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html bash_profile ], though the online version will be updated soon. Just think what else you could run like this!
Note 1: I had to edit the toprc file out due to this site can't handle that (uploads/including code). So you can grab it from [ http://www.askapache.com/linux-unix/bash-power-prompt.html my site ]
Note 2: I had to come back and edit again because the links weren't being correctly parsed
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"
}
Retrieved from:
https://en.wikipedia.org/wiki/Fork_bomb
More info:
http://stackoverflow.com/questions/991142/how-does-this-bash-fork-bomb-work
Checks HDD for bad sectors, just like scandisk or chkdisk under some other operating system ;-).
Sometimes you want to write the script output to stdout but you need to send it to email.
If you use:
$ var="$( ls / )";
$ echo -e "$var";
works but, you need to wait the script terminate to bufferize then print the output var;
With this way, you can use/work/print the output before the variable receive all the output content, then after it you can use the variable for anything else, like send email.
In the sample output, I pressed ctrl+r and typed the letters las. I can't imagine how much typing this has saved me.
