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Commands tagged stdin from sorted by
Terminal - Commands tagged stdin - 6 results
col() { awk '{print $('$(echo $* | sed -e s/-/NF-/g -e 's/ /),$(/g')')}'; }
2014-06-05 18:01:31
User: tekniq
Functions: awk col echo sed
0

Something I do a lot is extract columns from some input where cut is not suitable because the columns are separated by not a single character but multiple spaces or tabs. So I often do things like:

... | awk '{print $7, $8}'

... which is a lot of typing, additionally slowed down when typing symbols like '{}$ ... Using the simple one-line function above makes it easier and faster:

... | col 7 8

How it works:

The one-liner defines a new function with name col

The function will execute awk, and it expects standard input (coming from a pipe or input redirection)

The function arguments are processed with sed to use them with awk: replace all spaces with ,$ so that for example 1 2 3 becomes 1,$2,$3, which is inserted into the awk command to become the well formatted shell command: awk '{print $1,$2,$3}'

Allows negative indexes to extract columns relative to the end of the line.

Credit: http://www.bashoneliners.com/oneliners/oneliner/144/

VAR=$(head -5)
2014-04-05 13:45:18
User: rodolfoap
Functions: head
Tags: read stdin head,
-2

Reads n lines from stdin and puts the contents in a variable. Yes, I know the read command and its options, but find this logical even for one line.

command <<< word
2012-02-29 03:14:54
User: adeverteuil
Functions: command
Tags: bash stdin
10

Don't do this:

echo word | command

Using a bash "here strings" and "here documents" look leeter than piping echo into the command. Also prevents subshell execution. Word is also expanded as usual.

read -t 0.1 -N 255
(echo foobar; echo farboo) | perl -E 'say[sort<>=~/./g]~~[sort<>=~/./g]?"anagram":"not anagram"'
2011-02-17 02:15:46
User: doherty
Functions: echo perl
2

This works by reading in two lines of input, turning each into a list of one-character matches that are sorted and compared.

ftp-latest <<< "cd /; cls -1 | tail -1 | xargs -I% echo get % | /PATH/TO/ftp-latest"
2010-10-07 17:59:45
User: sputnick
Functions: ftp
0

Require lftp and this script to work (adapt path and credentials as needed):

echo $'#!/bin/bash\n# coded by sputnick under GPL 20101007\nlftp -u user,passwd remoteuser@host.tld -e "$(cat)"' > /PATH/TO/ftp-latest; chmod +x !$