Linux shellscript combine all files without for loop

Question

I have hundreds of files in one directory, is there a simple command or pipes of command I can use to append them together? I don't want to use any loops.

Answer 1

cat * >/path/to/somewhere

don't do

cat * > toall.txt

because "toall.txt" is created before cat is started and you will get strange result, "cat"ing toall.txt into toall.txt.

if want cat in the current directory, you should use

cat [some_globbing] > file #or
cat * > .dotted_file

.dotted_file is not expanded by * globbing.

or for example

(ls *.txt | xargs cat ) > /some/file

Answer 2

If there aren't too many files:

cat * > /some/new/file

Otherwise:

find . -exec cat {} + > /some/new/file
find . -exec cat {} \; > /some/new/file

Answer 3

Similar to Ignatio's suggestion:

rm /the/output && find . -print0 | xargs -0 cat >> /the/output

Without using xargs, you're apt to blow your maximum command line length. Without using -print0, you'll potentially have problems with files that have weird chars (like spaces) in the names. But that's also GNU-specific.

Answer 4

This will append all files to outfile:

for file in !(outfile); do
        cat "$file" >> outfile
done    

You need to delete outfile first if it exists. This will however not catch the dot-files. If you want to catch those as well you can use the two patterns

.??* !(outfile)

to create your file list. It requires a dot-file to have at least length 3, hence excludes . and ..!