Get rid of multiple spaces/tabs in a text file

sed -i "s/\(\x09\{1,\}\)\|\( \{1,\}\)/ /g;s/\(\x09\{1,\}$\)\|\( \{1,\}$\)//g" brisati.txt
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!)
Sample Output
$ cat brisati.txt
[       ]<--one tab
[                       ]<--three tabs                    
[ ]<--one space
[   ]<--three spaces
$ sed -i "s/\(\x09\{1,\}\)\|\( \{1,\}\)/ /g;s/\(\x09\{1,\}$\)\|\( \{1,\}$\)//g" brisati.txt;cat brisati.txt
[ ]<--one tab
[ ]<--three tabs
[ ]<--one space
[ ]<--three spaces

By: knoppix5
2011-12-12 10:24:03

1 Alternatives + Submit Alt

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 '//'.
flatcap · 488 weeks ago
Wow, mighty! Thank you! One may want append "delete empty lines" ( ;/^$/d ) to this command too)
knoppix5 · 488 weeks ago
a bit overkill, when a shorterway to do it is just as good
chrismccoy · 488 weeks ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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