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a find and replace within text-based files
using find's exec option instead of a for loop and using sed's -i option for inplace replacement. no need to do the file swap.

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

Output system statistics every 5 seconds with timestamp
See man vmstat for information about the statistics. This does the same thing without the timestamp: $vmstat 5

Generate Random Text based on Length
Random text of length "$1" without the useless cat command.

put command in a loop to keep trying a connection
This will keep trying to reconnect your netcat connection can be used with SSH or Telnet, just substitute nc for ssh or telnet very useful for troubleshooting VPNs were you want to send continuous packets towards a destination to trace.

Python extract json

add repeated watermark to image

Join lines and separate with spaces
Read vmargs.txt, which is a text file that could either be DOS-style (\r\n) or UNIX-style (\n) line endings and join the lines with a space separator. Can this be shortened/made more elegant?

recurisvely md5 all files in a tree
Found this little gem here: http://info.michael-simons.eu/2008/10/25/recursively-md5sum-all-files-in-a-directory-tree/

find which of the zip files contains the file you're searching for
This command find which of your zip (or jar) files (when you have lots of them) contains a file you're searching for. It's useful when you have a lot of zip (or jar) files and need to know in which of them the file is archived. It's most common with .jar files when you have to know which of the .jar files contains the java class you need. To find in jar files, you must change "zip" to "jar" in the "find" command. The [internal file name] must be changed to the file name you're searching that is archived into one of the zip/jar files. Before run this command you must step into the directory that contains the zip or jar files.


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