When a teacher grants permission face to face, later usage may describe it as “shāfahanī.” When he issues a written authorization, the wording may describe a written ijāzah. In neither case does oral or written authorization alone imply that the actual hadith was heard directly.
“Shāfahanī bi-l-ijāzah”
“He authorized me orally.”
“Kataba ilayya bi-l-ijāzah”
“He wrote to authorize me.”
These are later technical uses of the verbs. When a teacher actually sends the text of the report in writing, that is separately considered under written transmission. A written authorization must not be confused with receipt of the written hadith itself.