Shell script issue with filenames containing spaces

Question

I understand that one technique for dealing with spaces in filenames is to enclose the file name with single quotes: \"\'\".

Why is it that the following code called

Answer 1

change the following line from

ls "'$f'"

into

ls "$f"

Answer 2

What about this ? =)

#!/bin/sh
for f in *; do
    printf -- '%s\n' "$f"
done

Answer 3

you're actually adding redundant "'" (which your echo invocation shows)

try this:

#!/bin/sh
for f in *
do
ls "$f"
done

Answer 4

Taking a closer look at the output of your echo.sh script you might notice the result is probably not quite the one you expected as every line printed is surrounded by ' characters like:

'file-1'
'file-2'

and so on.

Files with that names really don't exist on your system. Using them with ls ls will try to look up a file named 'file-1' instead of file-1 and a file with such a name just doesn't exist.

In your example you just added one pair of 's too much. A single pair of double quotes" is enough to take care of spaces that might contained in the file names:

#!/bin/sh
for f in *
do
  ls "$f"
done

Will work pretty fine even with file names containing spaces. The problem you are trying to avoid would only arise if you didn't use the double quotes around $f like this:

#!/bin/sh
for f in *
do
  ls $f # you might get into trouble here
done