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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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Convert embedded spaces in filenames to "_" (underscore)

Terminal - Convert embedded spaces in filenames to "_" (underscore)
ls -1 | grep " " | awk '{printf("mv \"%s\" ",$0); gsub(/ /,"_",$0); printf("%s\n",$0)}' | sh # rename filenames: spaces to "_"
2009-03-15 18:42:43
User: mpb
Functions: awk grep ls rename sh
Convert embedded spaces in filenames to "_" (underscore)

This command converts filenames with embedded spaces in the current directory replacing spaces with the underscore ("_") character.


There are 4 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

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What others think

this also does the trick:

ls|while read f;do mv "$f" "${f// /_}";done
Comment by elzapp 396 weeks and 4 days ago


for i in *\ *; do mv "$i" $(echo -n "$i" | sed 's/ /_/g'); done

Nice variable substition, elzapp!

Comment by flatcap 396 weeks and 4 days ago

Try this:

rename 'y/ /_/' *
Comment by goodevilgenius 396 weeks and 4 days ago

@goodevilgenius Who'd've thunk it

Comment by elzapp 396 weeks and 4 days ago

goodevilgenuius' good suggestion invokes the prename perl script provided by the 'perl' package, at least under Ubuntu/Debian. On my ubuntu system, the rename command is symlinked to prename, and the original, non-perl rename command, which is still useful, is known as rename.ul

See $man prename, $less `which prename` and $man rename.ul for more. :-)

Comment by bwoodacre 396 weeks and 4 days ago

Thanks for the comments. It's a great way to learn fu.

# before ls -1

big world keeps turning

bye bye


hello world

ls|while read f;do mv "$f" "${f// /_}";done

mv: `fred' and `fred' are the same file

# after ls -1





I think we need a ' | grep " " ' in there.

Comment by mpb 396 weeks and 4 days ago

@mbp no need for a grep, just replace the "ls" with ls "* *"

ls "* *"|while read f;do mv "$f" "${f// /_}";done
Comment by elzapp 396 weeks and 4 days ago

d'oh mpb even...

Comment by elzapp 396 weeks and 4 days ago

@elzapp I admire your intention (to reduce the command line length) but it does not work for me:

ls -1

big world keeps turning

bye bye



two spaces embedded

ls "* *"

ls: cannot access * *: No such file or directory

This works (for me):

ls | grep " " | while read f;do mv "$f" "${f// /_}";done # after ls -1






Comment by mpb 396 weeks and 3 days ago

flatcap's version seems the most straightforward to me, and it's the only one that works on my system (Cygwin)

Comment by Ben 396 weeks and 3 days ago

/me takes hat off for "detox". Not only does it sort out spaces, it removes other ugly characters and is recursive.

Very nifty!


Comment by mpb 396 weeks and 3 days ago
ls|awk '/ /{c=$1; for (i=2;i<=NF;i++) c=c "_" $i; system("mv \"" $0 "\" \"" c "\"")}'
Comment by point_to_null 395 weeks and 6 days ago

@point_to_null switched to "detox" already


Comment by mpb 395 weeks and 2 days ago

Your point of view

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