Android edit .conf file programmatically

I wish to add lines to a .conf file in the root folder progra开发者_运维问答mmatically from my app. My users will have root access, and my app's purpose is to help them edit a .conf file. Suggestions/tutorials?

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Editing root files cannot be done without root permission: How to create/write file in the root of the android device?

Your users would have to have rooted devices and give the application root permission.