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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 is 1 alternative - vote for the best!

Terminal - Alternatives

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What others think

this also does the trick:

ls|while read f;do mv "$f" "${f// /_}";done
Comment by elzapp 342 weeks and 1 day ago


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

Nice variable substition, elzapp!

Comment by flatcap 342 weeks and 1 day ago

Try this:

rename 'y/ /_/' *
Comment by goodevilgenius 342 weeks and 1 day ago

@goodevilgenius Who'd've thunk it

Comment by elzapp 342 weeks and 1 day 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 342 weeks and 1 day 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 342 weeks and 1 day 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 342 weeks and 1 day ago

d'oh mpb even...

Comment by elzapp 342 weeks and 1 day 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 342 weeks 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 342 weeks 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 341 weeks and 6 days ago
ls|awk '/ /{c=$1; for (i=2;i<=NF;i++) c=c "_" $i; system("mv \"" $0 "\" \"" c "\"")}'
Comment by point_to_null 341 weeks and 2 days ago

@point_to_null switched to "detox" already


Comment by mpb 340 weeks and 6 days ago

Your point of view

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