Question

I have a file like this:

This is a sentence.
This is another sentence.

I need to put a new line after each character, such that only one character appears on every line, e.g.:

T
h
i
s

i
s

a

s
e
n
t
e
n
c
e
.
T
h
i
s

i
s

a
n
o
t
h
e
r

s
e
n
t
e
n
c
e
.

• The file is in UTF-8 and contains many non-English characters.
• It does not matter if spaces or carriage returns have their own line.

How can I remove every character to a new line?

Answer 1

Using sed replace every character with itself followed by a newline:

sed 's/./\0\n/g' -i filename