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escape any command aliases
e.g. if rm is aliased for 'rm -i', you can escape the alias by prepending a backslash: rm [file] # WILL prompt for confirmation per the alias \rm [file] # will NOT prompt for confirmation per the default behavior of the command

Download mp3 files linked in a RSS podcast feed
Directly download all mp3 files of the desired podcast

Recursively list all of the files in a directory, group them by extension and calculate the average of the file sizes in each group
Here's an annotated version of the command, using full-names instead of aliases. It is exactly equivalent to the short-hand version. # Recursively list all the files in the current directory. Get-ChildItem -Recurse | # Filter out the sub-directories themselves. Where-Object { return -not $_.PsIsContainer; } | # Group the resulting files by their extensions. Group-Object Extension | # Pluck the Name and Count properties of each group and define # a custom expression that calculates the average of the sizes # of the files in that group. # The back-tick is a line-continuation character. Select-Object ` Name, Count, @{ Name = 'Average'; Expression = { # Average the Length (sizes) of the files in the current group. return ($_.Group | Measure-Object -Average Length).Average; } } | # Format the results in a tabular view, automatically adjusted to # widths of the values in the columns. Format-Table -AutoSize ` @{ # Rename the Name property to something more sensible. Name = 'Extension'; Expression = { return $_.Name; } }, Count, @{ # Format the Average property to display KB instead of bytes # and use a formatting string to show it rounded to two decimals. Name = 'Average Size (KB)'; # The "1KB" is a built-in constant which is equal to 1024. Expression = { return $_.Average / 1KB }; FormatString = '{0:N2}' }

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"

Generate a random password 30 characters long
According to the gpg(1) manual: --gen-random 0|1|2 count Emit count random bytes of the given quality level 0, 1 or 2. If count is not given or zero, an endless sequence of random bytes will be emitted. If used with --armor the output will be base64 encoded. PLEASE, don't use this command unless you know what you are doing; it may remove precious entropy from the system! If your entropy pool is critical for various operations on your system, then using this command is not recommended to generate a secure password. With that said, regenerating entropy is as simple as: $ du -s / This is a quick way to generate a strong, base64 encoded, secure password of arbitrary length, using your entropy pool (example above shows a 30-character long password).

Get your outgoing IP address
should be very consistent cause it's google :-)

Print a horizontal line
Replace the underscore with any other character. e.g. + or - or =

copy remote ssh session output to local clipboard
ssh from local to remote and pipe output of file to the local clipboard

Install pip with Proxy
Installs pip packages defining a proxy

Create a backup copy of a MySQL database on the same host
This should probably only be used for testing in a dev environment as it's not terribly efficient, but if you're doing something that might trash a DB and you still want the old data available, this works like a charm.


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