When you open files from the command line
open
$ open README.md
the default app for that filetype will be used. For me, README.md will be opened in VS Code.
README.md
If you have a different app in mind, you can specify it using the -a flag:
-a
$ open README.md -a Notes
This will open README.md in Mac's Notes app.
See man open for more details.
man open
Last updated 4 years ago