Commands by ktonga (1)

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summarize a list of IP addresses, verifying IP address and giving counts for each IP found
Working with lists of IP addresses it is sometimes useful to summarize a count of how many times an IP address appears in the file. This example, summarizeIP, uses another function "verifyIP" previously defined in commandlinefu.com to ensure only valid IP addresses get counted. The summary list is presented in count order starting with highest count.

Get number of users on a minecraft server
I'm flat-out surprised that minecraft directory services require servers install multiple modifications to their server code, when the directories could fetch this information on their own.

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

graphical memory usage
smem is very clever, it keeps in mind shared memory in its calculations!!! http://www.selenic.com/smem/

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Find broken symlinks and delete them
recursively deletes all broken symlinks using zsh globbing syntax.

Coping files, excluding certain files
Preserve file structure when coping and exclude some file o dir patterns

Dump a configuration file without comments or whitespace...
A short, *easy-er* to remember command for stripping whitespace and comments from a config file, (or any file for that matter). Remember regex as: slash, space, star. pound, slash, bar. pointy-hat, dollar. (or "caret, dollar" if you must) :-P

ettercap..
There weren't any one liners for ettercap on this site... tisk tisk :-) (of course you'll have to plugin your own values for the variables..)

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"

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