Christopher
Christopher

Reputation:

How do you send the output of ls to mv?

I know you can do it with a find, but is there a way to send the output of ls to mv in the unix command line?

Upvotes: 51

Views: 81956

Answers (13)

douwe
douwe

Reputation: 1

\ls *.png -tmQ1 | sed "s/^/viewnior /" > dw && chmod u+x dw && ./dw

The above uses ls because I needed things sorted by time. It inserts the command viewnior (to view .png files) (in your case the command would be mv) on each line and redirects the output to a file. That file is then made executable and each line in this file is a command like this: viewnior image.png. Next it executes the file. It may not be pretty but I find it easy to remember.

(The \ in \ls is there in case ls was aliased to something that may interfere.)

Upvotes: -1

Raman
Raman

Reputation: 19585

So this answer doesn't send the output of ls to mv but as @lhunath explained using ls is almost always the wrong tool for the job. Use shell globs or a find command.

For more complicated cases (often in a script), using bash arrays to build up the argument list from shell globs or find commands can be very useful. One can create an array and push to it with the appropriate conditional logic. This also handles spaces in filenames properly.

For example:

myargs=()
# don't push if the glob does not match anything
shopt -s nullglob
myargs+=(myfiles*)

To push files matching a find to the array: https://stackoverflow.com/a/23357277/430128.

The last argument should be the target location:

myargs+=("Some target directory")

Use myargs in the invocation of a command like mv:

mv "${myargs[@]}"

Note the quoting of the array myargs to pass array elements with spaces correctly.

Upvotes: -2

Alex Martelli
Alex Martelli

Reputation: 881557

One way is with backticks:

mv `ls *.boo` subdir

Edit: however, this is fragile and not recommended -- see @lhunath's asnwer for detailed explanations and recommendations.

Upvotes: 28

dbr
dbr

Reputation: 169543

Just use find or your shells globing!

find . -depth=1 -exec mv {} /tmp/blah/ \;

..or..

mv * /tmp/blah/

You don't have to worry about colour in the ls output, or other piping strangeness - Linux allows basically any characters in the filename except a null byte.. For example:

$ touch "blah\new|
> "
$ ls | xargs file
blahnew|:                  cannot open `blahnew|' (No such file or directory)

..but find works perfectly:

$ find . -exec file {} \;
./blah\new|
: empty

Upvotes: -2

Dennis Williamson
Dennis Williamson

Reputation: 359935

You shouldn't use the output of ls as the input of another command. Files with spaces in their names are difficult as is the inclusion of ANSI escape sequences if you have:

alias ls-'ls --color=always'

for example.

Always use find or xargs (with -0) or globbing.

Also, you didn't say whether you want to move files or rename them. Each would be handled differently.

edit: added -0 to xargs (thanks for the reminder)

Upvotes: 2

cjs
cjs

Reputation: 27191

None of the answers so far are safe for filenames with spaces in them. Try this:

for i in *; do mv "$i" some_dir/; done

You can of course use any glob pattern you like in place of *.

Upvotes: 8

lhunath
lhunath

Reputation: 125396

ls is a tool used to DISPLAY some statistics about filenames in a directory.

It is not a tool you should use to enumerate them and pass them to another tool for using it there. Parsing ls is almost always the wrong thing to do, and it is bugged in many ways.

For a detailed document on the badness of parsing ls, which you should really go read, check out: http://mywiki.wooledge.org/ParsingLs

Instead, you should use either globs or find, depending on what exactly you're trying to achieve:

mv * /foo
find . -exec mv {} /foo \;

The main source of badness of parsing ls is that ls dumps all filenames into a single string of output, and there is no way to tell the filenames apart from there. For all you know, the entire ls output could be one single filename!

The secondary source of badness of parsing ls comes from the broken way in which half the world uses bash. They think for magically does what they would like it to do when they do something like:

for file in `ls`  # Never do this!
for file in $(ls) # Exactly the same thing.

for is a bash builtin that iterates over arguments. And $(ls) takes the output of ls and cuts it apart into arguments wherever there are spaces, newlines or tabs. Which basically means, you're iterating over words, not over filenames. Even worse, you're asking bask to take each of those mutilated filename words and then treat them as globs that may match filenames in the current directory. So if you have a filename which contains a word which happens to be a glob that matches other filenames in the current directory, that word will disappear and all those matching filenames will appear in its stead!

mv `ls` /foo      # Exact same badness as the ''for'' thing.

Upvotes: 92

buster
buster

Reputation: 1151

#!/bin/bash

for i in $( ls * );
do
mv $1 /backup/$1
done

else, it's the find solution by sybreon, and as suggested NOT the green mv ls solution.

Upvotes: -2

sunny256
sunny256

Reputation: 9576

/bin/ls | tr '\n' '\0' | xargs -0 -i% mv % /path/to/destdir/

"Useless use of ls", but should work. By specifying the full path to ls(1) you avoid clashes with aliasing of ls(1) mentioned in some of the previous posts. The tr(1) command together with "xargs -0" makes the command work with filenames containing (ugh) whitespace. It won't work with filenames containing newlines, but having filenames like that in the file system is to ask for trouble, so it probably won't be a big problem. But filenames with newlines could exist, so a better solution would be to use "find -print0":

find /path/to/srcdir -type f -print0 | xargs -0 -i% mv % dest/

Upvotes: 2

Don Branson
Don Branson

Reputation: 13709

Backticks work well, as others have suggested. See xargs, too. And for really complicated stuff, pipe it into sed, make the list of commands you want, then run it again with the output of sed piped into sh.

Here's an example with find, but it works fine with ls, too:

http://github.com/DonBranson/scripts/blob/f09d24629ab6eb3ce509d4d3078818430306b063/jarfinder.sh

Upvotes: 0

sybreon
sybreon

Reputation: 3156

Check out find -exec {} as it might be a better option than ls but it depends on what you're trying to achieve.

Upvotes: 4

Craig Wright
Craig Wright

Reputation: 1605

Not exactly sure what you're trying to achieve here, but here's one possibility:

The "xargs" part is the important piece everything else is just setup. The effect of this is to take everything that "ls" outputs and add a ".txt" extension to it.

$ mkdir xxx  # 
$ cd xxx
$ touch a b c x y z
$ ls
a  b  c  x  y  z
$ ls | xargs -Ifile mv file file.txt
$ ls
a.txt  b.txt  c.txt  x.txt  y.txt  z.txt
$

Something like this could also be achieved by:

$ touch a b c x y z
$ for i in `ls`;do mv $i ${i}.txt; done
$ ls
a.txt  b.txt  c.txt  x.txt  y.txt  z.txt
$

I sort of like the second way better. I can NEVER remember how xargs works without reading the man page or going to my "cute tricks" file.

Hope this helps.

Upvotes: 6

Brandon Peterson
Brandon Peterson

Reputation: 405

You surround the ls with back quotes and put it after the mv, so like this...

mv `ls` somewhere/

But keep in mind that if any of your file names have spaces in them it won't work very well.

Also it would be simpler to just do something like this: mv filepattern* somewhere/

Upvotes: -3

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