Set the oven to 375°F (190°C). Line a baking sheet with parchment paper.
Open the crescent roll can and separate the dough into 8 triangles.
Place one hot dog on the wide end of each triangle and roll the dough toward the tip. If using cocktail sausages, cut each triangle into two strips and wrap one sausage in each strip.
Arrange the wrapped hot dogs seam-side down on the prepared baking sheet. Brush lightly with melted butter and sprinkle with sesame seeds or poppy seeds, if desired.
Bake for 12–15 minutes, or until the crescent dough is golden brown and cooked through.
Let the pigs in a blanket cool slightly before serving. Enjoy warm with ketchup, mustard, or your favorite dipping sauce.