What is a post conviction writ?

Normally, in a criminal case a post conviction writ refers to a writ of habeas corpus filed in state or federal court. Because I am not a N.C. lawyer, I don't know if it has a specific meaning in your state.

I do not practice criminal law anymore (did quite a bit, though). There are several post-convictions proceedings. First, you have a direct appeal of your conviction to the court of appeals. A direct appeal only corrects errors that occurred at trial such as improper jury instructions, evidence was admitted when it should not have been and/or vice-versa, indictment defective, etc. If there are issues in your case that are not properly raised on direct appeal, these issues can be raised in a Motion for Appropriate Relief. If you do not file your direct appeal in time, you can ask the court of appeals to hear your case through a Petition for a Writ of Certiorari. Without getting into the federal system, if you have serious constitutional issues and your state avenues have been exhausted, you can file in federal court a writ for habeas corpus. The federal rules are very complex regarding this.