Commands by Dark006 (2)

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Lookup your own IPv4 address

How to run a command on a list of remote servers read from a file
The important thing to note in this command, is the "-n" flag.

check open ports without netstat or lsof

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Top 10 Memory Processes
It displays the top 10 processes sorted by memory usage

Open Vim with two windows
: new command allow to split a Vim screen in two separate windows. Each window can handle its own buffer. Passing the -c new options when Vim start cause to split screen automatically.

list files recursively by size

Tricky implementation of two-dimensional array in Bash.
Since Bash doesn't support two-dimensional arrays, you can limit your columns length by some big enough constant value ( in this example 100 ) and then index the array with i and j, or maybe write your own get() and set() methods to index the array properly like I implemented for example ( see Sample output ). For example for i=0 and j=0...99 you'll pick up one of 100 elements in the range [0,99] in the one-dimensional array. For i=1 and j=0...99 you'll pick up one of 100 elements in the range [100,199]. And so on. Be careful when using this, and remember that in fact you are always using one-dimensional array.

network usage per process
Nethogs groups bandwidth by process.

run a command whenever a file is touched
This is useful if you'd like to see the output of a script while you edit it. Each time you save the file the command is executed. I thought for sure something like this already exists - and it probably does. I'm on an older system and tend to be missing some useful things. Examples: $ ontouchdo yourscript 'clear; yourscript somefiletoparse' Edit yourscript in a separate window and see new results each time you save. $ ontouchdo crufty.html 'clear; xmllint --noout crufty.html 2>&1 | head' Keep editing krufty.html until the xmllint window is empty. Note: Mac/bsd users should use stat -f%m. If you don't have stat, you can use perl -e '$f=shift; @s=stat($f); print "$s[9]\n";' $1


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