Order all files by size using find

Question

As practice I need to complete a script that orders all filles by size with a given extension(.txt for example) including those in subdirectories too.

For example; 
./ex1.sh einstein txt
einstein/copyright.txt
einstein/do-how.txt
einstein/etext9/bil11.txt
einstein/etext9/2ws271.txt
einstein/etext9/liber11.txt
einstein/etext0/bib0010h/Readme.txt
einstein/etext0/kknta10.txt

I can't use du or other advanced commands. At some point I need to use find, I tried something like this

find -depth - type f -name "*.$extension" | sort ....

but this hasn't work really well, as i don't really know how to sort them by size, only result i get is sorted by name.

I was looking for an output similar to ls -lhS but including subdirectories.

Answer 1

The only sorting that any of the finds can do AFAIK is to have contents appear before the containing directory (the -depth option). You will have use something else to sort on size.

If you have GNU find, try:

find . -type f -iname "*.$extension" -printf "%s %p\n" | sort -n | sed 's/^[0-9]* //'

-printf "%s %p\n" prints the size and file path, then we sort numerically, and then strip the size using sed.

Answer 2

i use

   find . -type f -iname "*.$extension" -print0 | xargs -0 ls -lS

this works fine for me

Answer 3

With zsh:

printf '%s\n' **/*.$extension(D.oL)

To get a GNU ls -lh-type output, with GNU ls:

ls -Ulhd -- **/*.$extension(D.oL)

Or if the list is too large:

autoload zargs # best in ~/.zshrc
zargs --eof= -- **/*.$extension(D.oL) '' ls -Ulhd --

Or

printf '%s\0' **/*.$extension(D.oL) | xargs -r0 ls -Ulhd --

If for some reason, you do need to use find, you can always do:

printf '%s\0' ./**/*.$extension(D.oL) | xargs -r0 sh -c '
  exec find "$@" -prune ...' sh

Answer 4

find includes an option -printf which allows you to format what to output about your results, and how to output them. One of possibilities listed in the documentation for that option (see the man page) is %s for a file's size in bytes. Thus, you can add to your find command something like `-printf "%s %p\n".

Answer 5

Addition to muru's answer

You can use -exec du '{}' ';' inplace of -printf "%s %p" and still produces same format. So the final command be like

find . -type f -iname "*.$extension" -exec du '--' '{}' ';' | sort -n | sed 's/^[0-9]* //'

Explanation for the -exec du '-b' '--' '{}' ';'

1. -exec flag tells find to execute command (which is du) with {} occurence in arguments replaced with file path
2. '-b' tells du command to output bytes amount instead in kilobytes
3. '--' is a (flag? I need help about what this named) which signals ends of options and the rest of arguments is positional argument. One example where this needed is doing anything with file ambiguously named as option like -whatever
4. '{}' going back to point 1. find will substitute this with file path
5. ";" tells for find command that arguments for -exec is ended and can process the rest of arguments normally