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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.
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I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Get rid of multiple spaces/tabs in a text file

Terminal - Get rid of multiple spaces/tabs in a text file
sed -i "s/\(\x09\{1,\}\)\|\( \{1,\}\)/ /g;s/\(\x09\{1,\}$\)\|\( \{1,\}$\)//g" brisati.txt
2011-12-12 10:24:03
User: knoppix5
Functions: sed
Get rid of multiple spaces/tabs in a text file

This command does the following:

- converts any sequence of multiple spaces/tabs to one space only

- completely removes any space(s)/tab(s) at the end of each line

(If spaces and tabs are mixed in a sequence i.e. [tab][tab][space][tab], you have to execute this command twice!)


There are 2 alternatives - vote for the best!

Terminal - Alternatives
sed -i "s/\s*/ /g;s/\s*$//" input_file
2011-12-12 10:58:33
User: gitterrost4
Functions: sed

A much shorter version of this command.

Know a better way?

If you can do better, submit your command here.

What others think

Hmm. The shortest I can make that is:

sed -i 's/\s\+/ /g;s/\s*$//' file.txt

(and it only needs to be run once!

There are two sed clauses:

"s/\s\+/ /g" : find one or many whitespace characters '\s' and replace them with a single space, g = globally (as many times as needed).

"s/\s*$//" : find one or many whitespace characters '\s' at the end of the line '$' and replace them with nothing '//'.

Optionally, if you want to clear the leading whitespace, try:

sed -i 's/\s\+/ /g;s/^\s*//;s/\s*$//' file.txt

"s/^\s*//" : find one or many whitespace characters '\s' at the beginning of the line '^' and replace them with nothing '//'.

Comment by flatcap 260 weeks and 3 days ago

Wow, mighty! Thank you!

One may want append "delete empty lines" ( ;/^$/d ) to this command too)

Comment by knoppix5 260 weeks and 3 days ago

a bit overkill, when a shorterway to do it is just as good

Comment by chrismccoy 260 weeks and 3 days ago

Your point of view

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