Concatenate multiple files but include filename as section headers

Question

I would like to concatenate a number of text files into one large file in terminal. I know I can do this using the cat command. However, I would like the filename of each fi

Answer 1

This should do the trick:

for filename in file1.txt file2.txt file3.txt; do
    echo "$filename"
    cat "$filename"
done > output.txt

or to do this for all text files recursively:

find . -type f -name '*.txt' -print | while read filename; do
    echo "$filename"
    cat "$filename"
done > output.txt