Pass a value for an input prompt

Question

I do unzip my.zip and if files already exists it asks replace myfile.ext [y]es, [n]o, [A]ll, [N]one, [r]ename:

How can I force input for when the command prompts for input? I am aware unzip may have force flag but I am interested in passing an input.

Solution

I think you're looking for the yes command :

yes | unzip my.zip

It sends y to the output again and again. If you want to send something else, specify it as the argument:

yes n | unzip my.zip

You can also use echo if there's only one question:

echo no | unzip my.zip