Commands using head (314)

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no # comments, blank lines, white space. # can start in any column
The shortest and most complete comment/blank line remover... Any line where the first non-whitespace character is # (ie, indented # comments), and all null and blank lines are removed. Use the alias as a filter: $ noc /etc/hosts or $ grep server /etc/hosts | noc Change to nawk depending awk versions.

Text graphing ping output filter
Nasty perl one-liner that provides a sparkline of ping times. If you want a different history than the last 30, just put that value in. It (ab)uses unicode to draw the bars, inspired by https://github.com/joemiller/spark-ping . It's not the most bug-free piece of code, but what it lacks in robustness it makes up for in capability. :) If anyone has any ideas on how to make it more compact or better, I'd love to hear them. I included a ping to google in the command just as an example (and burned up 10 chars doing it!). You should use it with: $ ping example.com | $SPARKLINE_PING_COMMAND

Stat each file in a directory
Possible simplification of egrep-awk-sort with find and -exec with xargs.

intersection between two files

Calculate days on which Friday the 13th occurs
Simply change the years listed in the first seq, and it will print out all the months in that span of years that have Friday the 13ths in them.

draw honeycomb
$ tput setaf 1 && tput rev && seq -ws "___|" 81|fold -69|tr "0-9" "_" && tput sgr0 $ $ # (brick wall)

extract column from csv file
extracts the 5th column using the delimiter ','

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

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"

Display formatted routes


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