[SOLVED] How to set natural sort in Linux by default?

ddenial · 08-17-2018, 02:07 AM

Hello

How to set Linux so that the files are displayed in natural sort order?

By default file are listed in this way:
blah_10.txt
blah_11.txt
blah_1.txt
blah_20.txt
blah_2.txt

But I want to sort them by naturally, like
blah_1.txt
blah_2.txt
blah_10.txt
blah_11.txt
blah_20.txt

By using 'ls -lv', I can sort files in a natural way. But, it is not applied to others like loops and find command.

Is there a way to set natural sort as default in Linux?

Thanks

lougavulin · 08-17-2018, 04:08 AM

I don't know anyway to do this as default for all commands...

It will be by command :
* sort with -V
* ls with - v as you saw
* loop for with do like that : for F in blah_{1..20}.txt; do ...
* find, you have to use sort command

pan64 · 08-17-2018, 04:16 AM

you can influence sorting by LC_ (locale) variables. But actually what you have got is the natural sorting, just you don't like it.
If you wish "better" result you need to rename files like:
blah_01.txt
blah_02.txt
blah_10.txt
blah_11.txt
blah_20.txt
ls itself cannot handle that non-natural partially alphabetic and partially numeric sorting (yes, -v will try to simulate something you expected).
And also if you wish you can implement your own sorting algorithm (or script) which will work as you wish.

Turbocapitalist · 08-17-2018, 04:26 AM

Quote:

Originally Posted by pan64

If you wish "better" result you need to rename files like:
blah_01.txt
blah_02.txt
blah_10.txt
blah_11.txt
blah_20.txt

It's rather easy to rename them using the sprintf() function, even if there are many:

Code:

rename -n 's/_([0-9]+)\./sprintf("_%02d.",$1)/e' blah*.txt

The %02d adds a leading zero when the number is a single digit. You can add any number of leading zeros %03d, %05d, etc. The s/// is a normal regex substitution, but adding the e modifier makes the substituted component accept perl expressions, such as a simple sprintf()

syg00 · 08-17-2018, 04:40 AM

With our standard caveat - ...
IF you have the perl version of rename.

As to "version" sorting, I have found it really useful, but there have been corner cases (which I can't remember specifically) where it didn't work as expected. So buyer beware.

ddenial · 08-17-2018, 05:53 AM

I get this sorting problem when recursing files in a directory using 'for' loop.

I solved this by using ls command in for loop.

Code:

$ shopt -s globstar
$ for i in "$(ls -v **/*.{txt,rtf})" ; do echo "$i" ; done
blah_1.txt
blah_2.txt
blah_10.txt
blah_11.txt
blah_20.txt
subdir/aaa/file01.rtf
subdir/aaa/file03.rtf
subdir/aaa/file020.rtf
subdir/file1.txt
subdir/file02.txt
subdir/file3.txt
subdir/file004.txt
subdir/file5.txt

Hope it always works flawlessly.

Thank you all.

pan64 · 08-17-2018, 05:55 AM

Quote:

Originally Posted by ddenial

Hope it always works flawlessly.

No, unfortunately it doesn't. Especially when filename(s) contain space(s) or other "strange" characters.

ddenial · 08-17-2018, 06:16 AM

Quote:

Originally Posted by pan64

No, unfortunately it doesn't. Especially when filename(s) contain space(s) or other "strange" characters.

Oh!

I guess I've to forget about natural sort and let Linux do its way. That will be safe.

syg00 · 08-17-2018, 06:31 AM

Do some testing - the quotes should (might ?) protect the special characters.

lougavulin · 08-17-2018, 06:35 AM

One way to manage strange characters and space is to replace loop for with while read

Code:

while read File; do echo "$File"; done < <(ls -1v **/*.{txt,rtf})

ddenial · 08-17-2018, 06:51 AM

Quote:

Originally Posted by lougavulin

One way to manage strange characters and space is to replace loop for with while read

Code:

while read File; do echo "$File"; done < <(ls -1v **/*.{txt,rtf})

This works perfectly well. Thanks