Question

I’m not sure if this is possible in one line (i.e., without writing a script), but I want to run an ls | grep command and then for each result, pipe it to another command.

To be specific, I’ve got a directory full of images and I only want to view certain ones. I can filter the images I’m interested in with ls | grep -i <something>, which will return a list of matching files. Then for each file, I want to view it by passing it in to eog.

I’ve tried simply passing the results in to eog like so:

eog $(ls | grep -i <something>)

This doesn’t quite work as it will only open the first entry in the result list.

So, how can I execute eog FILENAME for each entry in the result list without having to bundle this operation into a script?

Edit: As suggested in the answers, I can use a for loop like so:

for i in 'ls | grep -i ...'; do eog $i; done

This works, but the loop waits to iterate until I close the currently opened eog instance.

Ideally I’d like for n instances of eog to open all at once, where n is the number of results returned from my ls | grep command. Is this possible?

Thanks everybody!

Answer 1

Try looping over the results:

for i in `ls | grep -i <something>`; do
    eog $i
done

Or you can one-line it:

for i in `ls | grep -i <something>`; do eog $i; done

Edit: If you want the eog instances to open in parallel, launch each in a new process with eog $i &. The updated one-liner would then read:

for i in `ls | grep -i <something>`; do (eog $i &); done