Commands by k2s (3)

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Find size in kilobyte of files that are deleted but still in use and therefore consumes diskspace

Watch the progress of 'dd'
dcfldd is a forensic version of dd that shows a process indicator by default.

get a fresh commandlinefu-item each day as motd
Commandline-fu often has little tricks that I always forget. By adding this to the root-cron (sudo crontab -e) I lean a new trick every day.

display typedefs, structs, unions and functions provided by a header file
will display typedefs, structs, unions and functions declared in 'stdio.h'(checkout _IO_FILE structure). It will be helpful if we want to know what a particular header file will offer to us. Command 'cpp' is GNU's C Preprocessor.

Know which version dpkg/apt considers more recent
Compares two versions with dpkg. It is not always obvious what version dpkg/apt will consider to be more recent. Operators include the following : * These treat an empty version as earlier than any version: lt le eq ne ge gt. * These treat an empty version as later than any version: lt-nl le-nl ge-nl gt-nl. * These are provided only for compatibility with control file syntax: < > >. This command doesn't output anything. It only returns with status 0 or 1, hence the echo "y" || echo "n" to get an output.

Disassemble some shell code
This one liner takes the shell code that you can grab off of the web and disassemble it into readable assembly so you can validate the code does what it says, before using it. The shell code in the above example is from http://www.shell-storm.org/shellcode/files/shellcode-623.php You can replace "-s intel" with "-s att" to get AT&T format disassembly.

Delete Empty Directories
Deletes empty directories and prints an error if directory is not empty.

shorten url using curl, sed and is.gd
Just create a function in your .bashrc like this shorturl() { curl -s -d URL="$1" http://is.gd/create.php | sed '/Your new shortened/!d;s/.*value="\([^"]*\)".*/\1/' }

Print diagram of user/groups
Parses /etc/group to "dot" format and pases it to "display" (imagemagick) to show a usefull diagram of users and groups (don't show empty groups).

Chrome sucks


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