recursive 'ls' giving absolute filenames

Question

When I do 'ls -R' in a directory, I get something like

./dir1
dir2 file1.txt file2.txt

./dir1/dir2
file3.txt file4.txt

but I would like a command that gives me

./dir1/file1.txt
./dir1/file2.txt
./dir1/dir2/file3.txt
./dir1/dir2/file4.txt

such that I can use it in a for-loop to process all files.

Answer 1

You want find(1). This will do exactly what you want. You can also specify various filter conditions such as file type (don't include directories), newer than the time stamp on a given file etc. The man page will describe these in more detail.

Also, take a look at the -exec option; you may be able to use this instead of iterating over the output.

Answer 2

If you're using bash ≥4 or zsh, you can make the shell do recursive globbing: the ** wildcard matches directories at any depth. In bash, you need to enable the feature with shopt -s globstar (in zsh, it's always enabled).

for x in **/*.txt; do …

If you need your script to be portable to other shells, use the find command, it's exactly the right tool for the job. Note that find is an external command that can work in two ways: it can generate a list of files, and it can execute commands for each file. If you want to execute a command for each file, use -exec:

find . -type f -name '*.txt' -exec chmod a+r {} +