In some dialects spoken in the western part of Japan, you can elongate the last vowel of the masu-stem to make an imperative form:
- 歩きい。 (dialect) = 歩け。 Walk.
- 見い。 (dialect) = 見ろ。 Watch.
- [待ちい]{LHL}。 (dialect) = [待て]{HL}。 Wait.
- [食べえ]{LHL}。 (dialect) = [食べろ]{LHL}。 Eat.
(From my personal experience, I feel this is mainly used in Chugoku/Shikoku region, but I may be wrong. See 西日本方言#文法)
You can attach various sentence-end particles like な, や, or よ, as usual.
(Attaching な to this kind of imperative may be specific to Osaka dialect. I found this article: 「大阪方言の命令形」に後接する終助詞ヤ・ナ (PDF))
- すぐ来【き】いや。 (dialect) = すぐ来【こ】いよ。 Come at once.
- はよう寝えよ。 (dialect) = はやく寝ろよ。 Go to bed now.
- [待ちいな]{LHLL}。 (dialect) = [待てよ]{HLL}。 Wait.
Note that you can use な to form positive imperative in standard Japanese, too. But the last vowel of the masu-form is not elongated in the standard Japanese. Also see the difference in accents.
Using な in positive instead of negative imperative (e.g. 行きな)
- [待ちな]{LHH}。 = [待て]{HL}。
- [食べな]{LHH}。 = [食べろ]{LHL}。