Commands using passwd (18)

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find an unused unprivileged TCP port
perl-less way

drop first column of output by piping to this

Create a false directory structure for testing your commands
This will make a false directory with the same file names as whatever directory you choose. This is wise to use when testing scripts that alter contents, filenames, or move files. I wrote this after an OOPS I made when renaming a directory of JPGs, PNGs, PSDs that were mixed. I recommend this as I lost over 2000 vacation pictures and some graphics I designed for software and web sites. :( NOTE: This only creates name copies, that data itself is not copied.

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"

Apply, in parallel, a bc expression to CSV
Define a function that applies bc, the *nix calculator, with the specified expression to all rows of the input CSV. The first column is mapped to {1}, second one to {2}, and so forth. See sample output for an example. This function uses all available cores thanks to GNU Parallel. Requires GNU Parallel

Search trought pidgin's conversation logs for "searchterm", and output the result.
will search trought pidgin conversation logs for "searchterm", and output them stripping the html tags. The "sed" command is optionnal if your logs are stored in plain text format.

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"

output length of longest line
If your wc does not have the -L option, you can use awk.

List files
Shortcut to list files in the current path.

Clear cassandra snapshots that are older than 30 days
Better than: $ nodetool clearsnapshot


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