Append or create a file, in one command?

Question

Very simple task: grab an output and redirect it to a file, using shell.

Now, I need to create the file if it does not exist, or if it exist, I need to append data

If I use output > file.txt I get data overwritten at each access. Not what I want. If I use output >> file.txt I get an error, because shell is trying to access the file while, I need it to create it first (it does not exist yet).

Is there a way to say in one line to create it, if the file doesn't exist, and append data or append only if the file does exist already?

I can just do that using an if-else (if file exist use >> otherwise use >), and I would like to avoid to complicate my code, if there is an easier way.

Answer 1

to create or append to a file in bash, you can use >>.

echo "sample text" >> sample_file
echo "append text" >> sample_file