Bring a large pot of water to boil. Add the salt to the water after you cook the asparagus.
Add the asparagus to the boiling water and cook for 3 minutes. Remove with a wire mesh strainer or slotted spoon and reserve.
In a large skillet, over medium heat, sauté the onion in the olive oil until golden. Add the asparagus and sauté together for a few minutes and then add the shrimp. After another minute (longer if the shrimp is not pre-cooked), add the white wine. Add some salt and cook the combined ingredients over medium heat for two additional minutes.
Cook the pasta until al dente (about 2 minutes less than package directions), and retain 1 cup of the cooking water. Drain the pasta and add it to the shrimp and asparagus. Cook together for 1 minute, adding the retained cooking water as needed to make sure the pasta is moist and well coated. Serve immediately.