Bash variables with space (directories)

Question

I'm trying to echo all of the files in /foo while preserving the spaces within listed directories. Currently, a directory titled "bar1 bar2" will echo out as /path/to/foo/bar1/ then /bar2 then file.txt all on new lines. I need it to echo /path/to/foo/bar1 bar2/file.txt or /path/to/foo/bar1\ bar2/file.txt.

for file in $(find /path/to/foo/ -type f); do
  if [[ ... ]]; then
    echo "${file}"
  fi
done

Also tried:

for file in $(find /path/to/foo/ -type f | sed 's/ /\ /g'); do
  if [[ ... ]]; then
    echo "${file}"
    echo "$file" # variations i've tried
    echo $file   # variations i've tried
    echo ${file}
    otherCommand "${file}"
  fi
done

Answer 1

The problem is not with $file, it's with your usage of $(find…).

Both regular variables and $(…) process substitutions are subject to exactly the same kind of word-splitting. If you put $(find…) in double quotes, you get a single word with all output. If you don't, it will be split up at any whitespace – not just newlines or some other magical boundary that you probably expected.

An important part of the above is that backslash escapes are not processed when expanding the variable. It's just split at spaces and that's it.

(In other words, quoting $file didn't help because it never had the correct value in the first place!)

If you want to process all files recursively, your options are:

1. Read output from find in another way:

   find … -print | while read -r file; do
       echo "Got $file"
   done
   

   (Side note: File names may technically include newlines as well, so you might want to guard against that, as rare as it is:

   find … -print0 | while read -r -d "" file; do
       echo "Got $file"
   done
   

2. For small amounts of files, use bash's extended wildcards:

   shopt -s globstar
   for file in /path/to/foo/**; do
       echo "Got $file"
   done
   

With large directories, the advantage of find | while read is that it's streamed – your script will process results as they come. Meanwhile, both $(find) and wildcards have to collect everything into memory first, and only then return the (possibly massive) results.

On the other hand, using a pipe affects the entire while loop (not just the read command), so if you want to run anything that wants to read keyboard input, you have to manually provide it with the original stdin, e.g. vim "$file" < /dev/tty.