Script to Compare file size and delete the smaller

Shell Programming and Scripting
1

I am pretty new to scripting, so I appreciate your advice in advance.
The problem:

100 directories each containing 2 files that have the same extension with random names. The only attribute that discriminates the files is size. I would like to write a script that compares the files for size and deletes the smaller of the two. Thanks! - OSX, X11, bash

2

Is every pair of extensions unique? If not, it's hard to be 100% sure about anything.

3

The file names are random. The extension is the same (that is probably windows talk - sorry). I want the script to look in each directory and delete the smaller of the two files.
e.g.,

directory 1

asdfsdfo72392874983.nii.gz
asdfju07r-3828poafljkao.nii.gz

directory n

asdfopiw4-8rtlkjkkfa.nii.gz
ukjfsaoi04t0ifaf';lk'lk.nii.gz

4

I think I misunderstood. They're in 100 different directories, not in one pile, ergo they can be differentiated. Okay.

find /path/to/base -type d | while read LINE
do
        set -- $(ls -S "$LINE"/*.gz)
        [ "$#" -eq 2 ] || continue # Ignore folders that don't have 2 files

        echo "Keeping $1"
        echo rm "$2"
done
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5

Thank you so much! I'm embarrassed to say I've been struggling with that for 2 days. (I have a hard time asking for help :confused:). On the whole the script is beyond my vocabulary, but could you say how you actually made the size comparison here and how you got that output to "$1" and "$2".

6

It would probably be better to omit the quotes. The reason I say that is because no quotes makes it clear that the approach isn't intended to handle whitespace and pattern matching characters. As is, casual inspection may instill a false sense of security. Whatever those quotes protect against in the subshell will just bite in the parent shell.

Regards,
Alister

7

ls -S sorts by file size. The largest one comes first.

As for how I get it into $1 $2, try this:

set -- a b
echo $1
echo $2
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