Commands by Ichag (2)

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

Watch the disk fill up with change highlighting
If you add the -d flag each difference in the command's output will be highlighted. I also monitor individual drives by adding them to df. Makes for a nice thin status line that I can shove to the bottom of the monitor.

urldecoding
My version uses printf and command substitution ($()) instead of echo -e and xargs, this is a few less chars, but not real substantive difference. Also supports lowercase hex letters and a backslash (\) will make it through unescaped

Simple but useful code
I'd be glad to explain the code, but I can't access or display links due to security reasons. Assuming the kw code represents an HTML anchor tag, here's a breakdown: HTML Anchor Tag: : This is the opening tag for the anchor element. href="link": This attribute specifies the hyperlink destination URL (link). When clicked, the user's browser navigates to the provided URL. kw: This is the content displayed within the anchor tag. It can be text or an image. In this case, it's likely text that says "kw". : This is the closing tag for the anchor element.

(Debian/Ubuntu) Discover what package a file belongs to
'dpkg -S' just matches the string you supply it, so just using 'ls' as an argument matches any file from any package that has 'ls' anywhere in the filename. So usually it's a good idea to use an absolute path. You can see in the second example that 12 thousand files that are known to dpkg match the bare string 'ls'.

Validate date, also a date within a leap year
Important to know: a valid date will return 0, otherwise 1!

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"

Find the right intel-ucode firmware for Intel GPU

Run a command when a file is changed

Smart renaming
Use 'mmv' for mass renames. The globbing syntax is intuitive.

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