How to open a file with Gulp?

Question

css

Good day to all!
My project consists of the following folders/files:
materials
--maket.psd (or maket.sketch)
public
src
gulpfile.js
package.json

Question: When running the gulp command, how do I open a file from the maket.psd folder? And so that if it is already open, this task does not work.