How to split a text file into a fixed width file in tcsh?

Question

I need to read a text file and make it fit X amount of columns.

For example, if my text.txt contains:

ABCDEFGHIJK

the resulting file for a width of 4 should be:

ABCD
EFGH
IJK

Answer 1

Like this?

$ echo ABCDEFGHIJK | sed -r 's/(....)/\1\n/g'
ABCD
EFGH
IJK