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replace spaces in filenames with underscores

Terminal - replace spaces in filenames with underscores
rename 'y/ /_/' *
2009-06-27 22:20:47
User: signal9
Functions: rename
replace spaces in filenames with underscores

This command will replace all the spaces in all the filenames of the current directory with underscores. There are other commands that do this here, but this one is the easiest and shortest.


There are 2 alternatives - vote for the best!

Terminal - Alternatives
rename 's/ //g' *
zmv '* *' '$f:gs/ /_'
2013-03-23 00:58:52
User: khayyam

replace (any number of) space[s] with underscore.

rename 's/ /_/g' *

Know a better way?

If you can do better, submit your command here.

What others think

It should be noted that this "rename," while in Perl and portable, is not the standard rename utility on most systems.

Comment by dfego 388 weeks and 2 days ago

It depends on what you mean by "most systems." Specifically, at least under debian/ubuntu linux, on systems with perl installed, the /usr/bin/prename perl script (to which is being referred) overrides the util-linux rename command. To explicitly invoke either (again, on debian/ubuntu) the perl variant is named prename, and the util-linux (likely dfego's default) may be invoked is /usr/bin/rename.ul .

Comment by bwoodacre 388 weeks and 2 days ago

to do this purely in bash:

for file in *;do mv $file ${file// /_};done
Comment by elzapp 388 weeks and 1 day ago

Okay, not entirely purely, since the mv command is not a part of bash, but at least it would work without the rename.pl

Comment by elzapp 388 weeks and 1 day ago

Deja vu! rename overload! :-)

Doesn't anyone bother to grep the archive before posting command lines any more?

Comment by mpb 388 weeks and 1 day ago

I did grep the archive before I posted this and I did see several other commands that do the same as this one. However, this is, by far, the simplest and least complex command to date on here. So I thought I would drop it in. This is the first command I've submitted and it got into the "Hot this week" category! Yay!

Comment by signal9 387 weeks and 3 days ago

This depends on the Perl 'prename' command to be installed -- popular on Debian-based distributions, where /usr/bin/rename is a link to this file. The POSIX version of 'rename' doesn't do regular expressions, only one-time substring matches. 'rename oldstring newstring list_of_files' I.E.:

rename .htm .html *.htm

Comment by Mozai 283 weeks and 1 day ago

Funny enough,

ls -1 | while read file; do new_file=$(echo $file | sed s/\ //g); mv "$file" "$new_file"; done

is the only command that actually works for me on a a CentOS 5.6 machine.

Comment by nzimas 244 weeks and 6 days ago

the zsh eq would be:

zmv '* *' '$f:gs/ /_'

Comment by khayyam 193 weeks and 4 days ago

_(){ rename 'y/ /_/' "$*";}

Comment by Tiosam 89 weeks and 4 days ago

Your point of view

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