Question

A linux command I have outputs a list of files that look like this:

    folder/folder/folder/file_1
    folder_1/folder/folder/file2

I want to format this output so the following conditions are met:

• The last slash (/) is always replaced with three underscores
• Every slash except the last slash is replaced with one underscore
• Any underscore in a folder name is replaced with two underscores
• Any underscore in a filename is left the way it is

The above would look like:

    folder_folder_folder___file_1
    folder__1_folder_folder___file2

If you could also explain your solution that would be helpful. Thanks!

Answer 1

# Assume each line in a variable called $value
# Split the values up into dirname and basename
val_dir="${value%/*}"
val_base="${value##*/}"

# Replace underscores in dirname with two underscores
val_dir="${val_dir//_/__}"
# Replace slashes in dirname with single underscore
val_dir="${val_dir//\//_}"

# Re-join dirname and basename with three underscores
result="${val_dir}___${val_base}"