Question

This is my first post here although I’ve come here for solutions very very frequently!
I couldn’t find an answer to a question I have. Maybe I’m using the wrong tags in my search :/ Anyway, please, pardon me in advance if the question was asked before.

I want to create a small script to automatically upload photos and videos from a folder. I currently use a perl script called “flickr_upload”, found in the macports directory.

Let’s say I have 12 files in a directory. I want to split these 12 files in 3 batches of 4 files and launch 3 command-lines in parallel using xterm for example.

How can automatically split a list by just specifying the number of batches?

Regards

Edit: instead of writing:

flickr_upload photo01.jpg photo02.jpg photo03.jpg

I’d like to have:

flickr_upload photo01.jpg
flickr_upload photo02.jpg
flickr_upload photo03.jpg

by writing something like:

split -n 3 ./*.jpg | xterm flickr_upload -

Answer 1

xargs can do this for you.

for instance, seq 10 | xargs echo echos all 10 “arguments” at once. But seq 10 | xargs -n 3 echo does them 3 at a time:

1 2 3
4 5 6
7 8 9
10

I don’t know anything about flickr_upload or what “macports” might be, but presumably you can do this:

ls *jpg | xargs -n 3 flickr_upload