Commands by dirkr (1)

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Create a file of a given size in linux
if the fs support sparse file,using truncate can create sparse file. http://en.wikipedia.org/wiki/Sparse_file

Show account security settings
Show account security settings

create an incremental backup of a directory using hard links
dname is a directory named something like 20090803 for Aug 3, 2009. lastbackup is a soft link to the last backup made - say 20090802. $folder is the folder being backed up. Because this uses hard linking, files that already exist and haven't changed take up almost no space yet each date directory has a kind of "snapshot" of that day's files. Naturally, lastbackup needs to be updated after this operation. I must say that I can't take credit for this gem; I picked it up from somewhere on the net so long ago I don't remember where from anymore. Ah, well... Systems that are only somewhat slicker than this costs hundreds or even thousands of dollars - but we're HACKERS! We don't need no steenkin' commercial software... :)

aplay some whitenoise
Plays whitenoise from /dev/urandom.

Gets the english pronunciation of a phrase
Usage examples: say hello say "hello world" say hello+world

Random quote from Borat -- no html parsing
Turns out smacie.com has a text file containing every single one of the borat quotes, each one on a newline. This makes it very convenient, as this can be done without any sed-parsing, and uses less bandwitdth! Note that borate quotes are quite offensive, much more so than "fortunes-off"!

Weather on the Command line
Get your weather from a weather station just blocks from your home. Go to http://www.wunderground.com/wundermap/ and find a weather station near you. Click on a temperature bubble for that area. When the window pops up, click on hypertext link with the station ID, then on the bottom right of the page, click on the Current Conditions XML. Thats your link! Good luck!

get the latest version
to download latest version of "util", maybe insert a sort if they wont be shown in right order. curl lists all files on mirror, grep your util, tail -1 will gets the one lists on the bottom and get it with wget

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

list folders containing less than 2 MB of data
This command will search all subfolders of the current directory and list the names of the folders which contain less than 2 MB of data. I use it to clean up my mp3 archive and to delete the found folders pipe the output to a textfile & run: $ while read -r line; do rm -Rv "$line"; done < textfile


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