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Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

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

Summarize Apache Extended server-status to show longest running requests
Ever need to know why Apache is bogging down *right now*? Hate scanning Apache's Extended server-status for the longest running requests? Me, too. That's why I use this one liner to quickly find suspect web scripts that might need review. Assuming the Extended server-status is reachable at the target URL desired, this one-liner parses the output through elinks (rendering the HTML) and shows a list of active requests sorted by longest running request at the bottom of the list. I include the following fields (as noted in the header line): Seconds: How long the request is alive PID: Process ID of the request handler State: State of the request, limited to what I think are the relevant ones (GCRK_.) IP: Remote Host IP making the request Domain: Virtual Host target (HTTP/1.1 Host: header). Important for Virtual Hosting servers TYPE: HTTP verb URL: requested URL being served. Putting this in a script that runs when triggered by high load average can be quite revealing. Can also capture "forgotten" scripts being exploited such as "formmail.pl", etc.

Convert JSON to YAML (unicode safe)
If you tried the other Python version of Convert JSON to YAML and you end up with lines that has "!!python/unicode", this version of the command is for you.

Show sorted list of files with sizes more than 1MB in the current dir
Taken from here: http://linsovet.com/directory-usage-size-sorted-list

list block devices
Shows all block devices in a tree with descruptions of what they are.

Sum columns from CSV column $COL

list files recursively by size

Create several copies of a file
Copy a file to a range of other files.

check open ports without netstat or lsof


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