Commands by johnlane (1)

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commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Which Twitter user are you?
This will tell you which twitter user you are chronologically. For example, a number of 500 means you were the 500th user to create a twitter account.

list block devices
Shows all block devices in a tree with descruptions of what they are.

List files with full path
Prints contents of current directory with the full path prepended to each entry. You can add '-type f' if you don't want the directories to show up (for those less familiar with find). I can't believe ls doesn't have an option for this.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Identify differences between directories (possibly on different servers)
This can be much faster than downloading one or both trees to a common servers and comparing the files there. After, only those files could be copied down for deeper comparison if needed.

List top 20 IP from which TCP connection is in SYN_RECV state
List top 20 IP from which TCP connection is in SYN_RECV state. Useful on web servers to detect a syn flood attack. Replace SYN_ with ESTA to find established connections

Go to the next sibling directory in alphabetical order, version 2
Another version based on linkinpark342's contribution. Sometimes you have to browse your way through a lot of sub-directories. This command cd to the next sub-directory in alphabetical order. For example, if you have the directories "lectures/01-intro", "lectures/02-basic", "lectures/03-advanced" and so on, and your PWD is "02-basic", it jumps to "03-advanced".

April Fools' Day Prank
Add this to a fiend's .bashrc. PROMPT_COMMAND will run just before a prompt is drawn. RANDOM will be between 0 and 32768; in this case, it'll run about 1/10th of the time. \033 is the escape character. I'll call it \e for short. \e7 -- save cursor position. \e[%d;%dH -- move cursor to absolute position \e[4%dm \e[m -- draw a random color at that point \e8 -- restore position.

Look up the definition of a word
A bash function might also be useful: $ dict() { curl dict://dict.org/d:$1; } Or if you want less verbose output: $ dict() { curl -s dict://dict.org/d:$1 | perl -ne 's/\r//; last if /^\.$/; print if /^151/../^250/'; }

Mount Fat USB with RWX
after that, you can launch bash script in your usb drive in FAT32.


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