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Commands tagged oneliner

Commands tagged oneliner from sorted by
Terminal - Commands tagged oneliner - 11 results
while read line; do export $line; done < <(cat input)
2013-03-15 08:14:04
User: dario
Functions: cat export read
Tags: bash oneliner environment
0
Up
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export key-value pairs list as environment variables

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

OH=YEAH

FU=UUUU

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perl -e 'printf "00:16:3E:%02X:%02X:%02X\n", rand 0xFF, rand 0xFF, rand 0xFF'
2012-07-02 09:59:43
User: Gular
Functions: perl
Tags: perl oneliner random generate mac address
1
Up
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Perl One Liner to Generate a Random IP Address
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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
2012-02-24 23:40:02
User: bandie91
Tags: perl color curl oneliner commandlinefu rss ansi html2text xml2
3
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interactive rss-based colorful commandline-fu reader perl oneliner (v0.1)

required packages: curl, xml2, html2text

command is truncated, see 'sample output'

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
perl -MO=Deparse filename.pl | perltidy > new.pl
2011-11-16 18:54:30
User: kimmel
Functions: perl
Tags: perl oneliner beautify
0
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clean up syntax and de-obfuscate perl script

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

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perl -le 'print scalar gmtime shift' 1234567890
2011-11-16 18:37:11
User: kimmel
Functions: perl
Tags: Date manipulation perl oneliner epoch
1
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convert unixtime to human-readable

convert a unix timestamp to a human readable format.

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perl -MExtUtils::Installed -E 'say for ExtUtils::Installed->new()->modules()'
2011-11-16 17:26:47
User: kimmel
Functions: perl
Tags: perl oneliner
0
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Print a list of installed Perl modules

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

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cut -f 1 three-column.txt > first-column.txt
2010-07-11 10:13:45
User: postrational
Functions: cut
Tags: Text Processing bash extract oneliner while substitution
4
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Short one line while loop that outputs parameterized content from one file to another

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?

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awk '{print $1}' < three-column.txt > first-column.txt
2010-07-09 04:00:05
User: infinull
Functions: awk
Tags: Text Processing bash extract oneliner while substitution
3
Up
Down
Short one line while loop that outputs parameterized content from one file to another
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while read col1 col23; do echo $col1; done < three-column.txt > first-column.txt
2010-07-09 03:59:20
User: infinull
Functions: echo read
Tags: Text Processing bash extract oneliner while substitution
-5
Up
Down
Short one line while loop that outputs parameterized content from one file to another
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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
Tags: Text Processing bash extract oneliner while substitution
1
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Short one line while loop that outputs parameterized content from one file to another

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:

http://wiki.bash-hackers.org/syntax/pe

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

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awk 'NR==linenumber' filename
2010-07-06 05:17:29
User: rajarshi
Functions: awk
Tags: awk oneliner
-4
Up
Down
It outputs a given line from a file
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