Loop through all files in a directory and subdirectories using Bash [duplicate]

Question

I know how to loop through all the files in a directory, for example:

for i in *
do
  <some command>
done

But I would like to go through all the files in a directory, including (particularly!) all the ones in the subdirectories. Is there a simple way of doing this?

Answer 1

The find command is very useful for that kind of thing, provided you don't have white space or other special characters in the file names:

For example:

for i in $(find . -type f -print)
do
    stuff
done

The command generates path names relative from the start of the search (the first parameter).

As pointed out, this will fail if your filenames contain spaces or some other characters.

You can also use the -exec option which avoids the problem with spaces in file names. It executes the given command for each file found. The braces are a placeholder for the filename:

find . -type f -exec command {} \;

Answer 2

find and xargs are great tools for recursively processing the contents of directories and sub-directories. For example

find . -type f -print0 | xargs -0 command

will run command on batches of files from the current directory and its sub-directories. The -print0 and -0 arguments avoid the usual problems with filenames that contain spaces, quotes or other metacharacters.

If command just takes one argument, you can limit the number of files passed to it with -L1.

find . -type f -print0 | xargs -0 -L1 command

And as suggested by alexgirao, xargs can also name arguments, using -I, which gives some flexibility if command takes options. -I implies -L1.

find . -type f -print0 | xargs -0 -Iarg command arg --option