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Plaintext credentials sniffing with tcpdump and grep
Simple TCPDUMP grepping for common unsafe protocols (HTTP, POP3, SMTP, FTP)

Remove duplicate rows of an un-sorted file based on a single column
The command (above) will remove any duplicate rows based on the FIRST column of data in an un-sorted file. The '$1' represents a positional parameter. You can change both instances of '$1' in the command to remove duplicates based on a different column, for instance, the third: $ awk '{ if ($3 in stored_lines) x=1; else print; stored_lines[$3]=1 }' infile.txt > outfile.txt Or you can change it to '$0' to base the removal on the whole row: $ awk '{ if ($0 in stored_lines) x=1; else print; stored_lines[$0]=1 }' infile.txt > outfile.txt ** Note: I wouldn't use this on a MASSIVE file, unless you're RAM-rich ;) **

Mount FileVault sparsebundle image manually (e.g.: from TimeMachine disk).

Find how much of your life you've wasted coding in the current directory
Finds all C++, Python, SWIG files in your present directory (uses "*" rather than "." to exclude invisibles) and counts how many lines are in them. Returns only the last line (the total).

for ssh uptime
This will run them at the same time and timeout for each host in ten seconds. Also, mussh will append the ip addres to the beginning of the output so you know which host resonded with which time. The use of the sequence expression {1..50} is not specific to mussh. The `seq ...` works, but is less efficient.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

quick and dirty formatting for HTML code
Finds all the closing tags in a HTML document via non-greedy regex and adds a linefeed for easier reading/editing . sed -i.bak -r 's_(/[^>]*?>)_\1\n_g' filename.html . This will save a copy of filename.html as filename.html.bak and then add the linefeeds to the original file

randomize hostname and mac address, force dhcp renew. (for anonymous networking)
this string of commands will release your dhcp address, change your mac address, generate a new random hostname and then get a new dhcp lease.

Short one line while loop that outputs parameterized content from one file to another

Get all files of particular type (say, PDF) listed on some wegpage (say, example.com)
See man wget if you want linked files and not only those hosted on the website.


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