Commands by Dentorman (5)

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Cleanup a (source) text file, removing trailing spaces/tabs and multiple consecutive blank lines
I used this command (in addition to a code formatting tool) to "cleanup" a bunch of PHP files

List all active access_logs for currently running Apache or Lighttpd process
Ever logged into a *nix box and needed to know which webserver is running and where all the current access_log files are? Run this one liner to find out. Works for Apache or Lighttpd as long as CustomLog name is somewhat standard. HINT: works great as input into for loop, like this: $ for i in `lsof -p $(netstat -ltpn|awk '$4 ~ /:80$/ {print substr($7,1,index($7,"/")-1)}')| awk '$9 ~ /access.log$/ {print $9| "sort -u"}'` ; do echo $i; done Very useful for triage on unfamiliar servers!

Do quick arithmetic on numbers from STDIN with any formatting using a perl one liner.
Good for summing the numbers embedded in text - a food journal entry for example with calories listed per food where you want the total calories. Use this to monitor and keep a total on anything that ouputs numbers.

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

pretend to be busy in office to enjoy a cup of coffee
Dialog's gauge widget accepts progress updates on stdin. This version runs dialog once and updates it every second. There's no need to use timeout which causes screen flicker since it restarts dialog for each update.

grep (or anything else) many files with multiprocessor power
Parallel does not suffer from the risk of mixing of output that xargs suffers from. -j+0 will run as many jobs in parallel as you have cores. With parallel you only need -0 (and -print0) if your filenames contain a '\n'. Parallel is from https://savannah.nongnu.org/projects/parallel/

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

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

Find the package that installed a command

Cleanup firefox's database.
Sqlite database keeps collecting cruft as time passes, which can be cleaned by the 'vacuum;' command. This command cleans up the cruft in all sqlite files relating to the user you have logged in as. This command has to be run when firefox is not running, or it will exit displaying the pid of the firefox running.

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