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Find writable files
Have a grudge against someone on your network? Do a "find -writable" in their directory and see what you can vandalize! But seriously, this is really useful to check the files in your own home directory to make sure they can't inadvertently be changed by someone else's wayward script.

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

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"

Run a command on a remote machine
This counts the number of httpd processes running.

Pimp your less
# s = combine multiple lines of whitespace into 1 # x4 = set the tabstop to 4 instead of 8 # F = Exit if the output fits on 1 screen. This is similar to git diff # R = Raw control chars. This allows you to pipe colordiff straight to less. ie: alias sdi="svn diff | colordiff | less" # S = Chop off long lines # X = Dont send termcap init and deinit scrings to the terminal

identify exported sonames in a path
This provides a list of shared object names (sonames) that are exported by a given tree. This is usually useful to make sure that a given required dependency (NEEDED entry) is present in a firmware image tree. The shorter (usable) version for it would be $ scanelf -RBSq -F "+S#f" But I used the verbose parameters in the command above, for explanation.

Calculates the number of physical cores considering HyperThreading in AWK
Check whether hyperthreading is enabled or not. a better solution as nproc should work on all OS with awk

Monitor all DNS queries seen by the local machine

Delete empty directories
Recursively delete empty directories. Use with care.

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.


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