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Block the 6700 worst spamhosts
The above url contains over 6700 of the common ad websites. The command just pastes these into your /etc/hosts.

How to get an absolute value
Whenever we are only interested in difference between two numbers and not the positive/negative values we can use this in script.

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

Find default gateway

Remove executable bit from all files in the current directory recursively, excluding other directories
Useful if you have copied files from an OS without a permission structure (for example, DOS) and you need to disable all executable files but want to be able to descend into your directories.

Monitor logs in Linux using Tail
Works in Ubuntu, I hope it will work on all Linux machines. For Unixes, tail should be capable of handling more than one file with '-f' option. This command line simply take log files which are text files, and not ending with a number, and it will continuously monitor those files. Putting one alias in .profile will be more useful.

Create cheap and easy index.html file
If your admin has disabled Apache's directory index feature but you want to have a cheap way to enable it for one folder, this command will just create an index.html file with a link to each file in the directory (including the index.html file, which is not ideal but makes the command much simpler). The HTML isn't even remotely compliant, but it could easily be improved on. Also, the command needs to be run each time a file is added or removed to update the index.html file.

Find inside files two different patterns in the same line and for matched files show number of matched lines
The option -print0 for find and -0 for grep help prevent issue with weird characters or spaces in filenames. Furthermore with xargs there is no limited number of arguments that find can throw.

add lyrics

Simple XML tag extract with sed
Limited, but useful construct to extract text embedded in XML tags. This will only work if bar is all on one line. If nobody posts an alternative for the multiline sed version, I'll figure it out later...


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