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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Commands tagged oneliner from sorted by
Terminal - Commands tagged oneliner - 13 results
lsof -i -n -P | grep -e "$(ps aux | grep node | grep -v grep | awk -F' ' '{print $2}' | xargs | awk -F' ' '{str = $1; for(i = 2; i < NF; i++) {str = str "\\|" $i} print str}')"
2015-02-14 23:24:00
User: hochmeister
Functions: grep

us lsof, grep for any pid matching a given name such as "node".

echo "select a, b, c from table where a = 3;"| python -c "import sys;import sqlparse;print sqlparse.format(sys.stdin.read(), reindent=True, keyword_case='upper')"
2014-02-21 23:17:15
User: hide1713
Functions: echo python

You need to apt-get install python-sqlparse. This command simply formats a sql query and prints it out. It is very useful when you want to move a sql query from commandline to a shell script. Everything is done locally, so you don't need to worry about copying sql query to external websites.

while read line; do export $line; done < <(cat input)
2013-03-15 08:14:04
User: dario
Functions: cat export read

This exports all lines of input file as environment variables, assuming each line is like these:



perl -e 'printf "00:16:3E:%02X:%02X:%02X\n", rand 0xFF, rand 0xFF, rand 0xFF'
open R,"curl -s http://feeds2.feedburner.com/Command-line-fu|xml2|"; while(<R>){ chomp; m(^/rss/channel/item/title=) and do{ s/^.*?=//; ($t,$d,$l)=($_,undef,undef) }; m(^/rss/channel/item/description=) and do{ s/^.*?=//; push @d,$_ }; m(^/rss/channel/item
perl -MO=Deparse filename.pl | perltidy > new.pl
2011-11-16 18:54:30
User: kimmel
Functions: perl

This will create a new file with proper code formatting and all comments removed.

perl -le 'print scalar gmtime shift' 1234567890
perl -MExtUtils::Installed -E 'say for ExtUtils::Installed->new()->modules()'
2011-11-16 17:26:47
User: kimmel
Functions: perl
Tags: perl oneliner

Lists all the modules that were installed the "proper way". It also uses Perl 5.10(or higher)'s say command for less typing.

cut -f 1 three-column.txt > first-column.txt
2010-07-11 10:13:45
User: postrational
Functions: cut

There is a common command for outputting a field or list of fields from each line in a file. Why wouldn't you just use cut?

awk '{print $1}' < three-column.txt > first-column.txt
while read col1 col23; do echo $col1; done < three-column.txt > first-column.txt
while read l; do echo ${l%% *}; done < three-column-list.txt > only-first-column.txt
2010-07-09 03:42:56
User: zed
Functions: echo read

The above is an example of grabbing only the first column. You can define the start and end points specifically by chacater position using the following command:

while read l; do echo ${l:10:40}; done < three-column-list.txt > column-c10-c40.txt

Of course, it doesn't have to be a column, or extraction, it can be replacement

while read l; do echo ${l/foo/bar}; done < list-with-foo.txt > list-with-bar.txt

Read more about parameter expansion here:


Think of this as an alternative to awk or sed for file operations

awk 'NR==linenumber' filename