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

If you want to replace those ugly ==> <== with something else

tail -n +1 *.txt | sed -e 's/==>/\n###/g' -e 's/<==/###/g' >> "files.txt"

explanation:

tail -n +1 *.txt - output all files in folder with header

sed -e 's/==>/\n###/g' -e 's/<==/###/g' - replace ==> with new line + ### and <== with just ###

>> "files.txt" - output all to a file