C Function Return Array Of Pointers

But if i want to return the entire array i must return a pointer to a pointer.

C function return array of pointers. The size of the array is part of its type definition. Now consider the following function which will generate 10 random numbers and return them using an array name which represents a pointer i e address of first array element. In the above example we have used foo directly and it has been converted to a function pointer. Assigning a function to a function pointer.

Second point to remember is that c does not advocate to return the address of a local variable to outside of the function so you would have to define the local variable as static variable. The problem is we return address of a local variable which is not advised as local variables may not exist in memory after function call is over. For any further questions feel free to use the comments below. Function pointers can be initialized with a function and non const function pointers can be assigned a function.

So in this tutorial we learned about the different methods by which we can return an array from a c function. So passing it as a parameter or returning it will. Back in lesson 6 2 arrays part ii we mentioned that because copying large arrays can be very expensive c does not copy an array when an array is passed into a function. I think i understand now.

So in simple words functions can t return arrays in c. Hence it is clear from the output that the array return by the function func was successful. The above program is wrong it may produce values 10 20 as output or may produce garbage values or may crash. Like with pointers to variables we can also use foo to get a function pointer to foo.

However inorder to return the array in c by a function one of the below. C return array from function stackoverflow. Store the address of the first element of arr in ptr ptr arr. Second point to remember is that it is not good idea to return the address of a local variable to outside of the function so you would have to define the local variable as static variable.

An array in c is not the same type as in c. Not only can a pointer store the address of a single variable it can also store the address of cells of an array. Here is the main idea. Or the function can return a pointer to the first element of a static array defined inside the function which means the size of the array is fixed and the same array will be clobbered by a second call to the function.

Or the function can allocate the array on the heap which makes the caller responsible for deallocating it later. If you want to return a single dimension array from a function you would have to declare a function returning a pointer as in the following example int myfunction. I have to ask a follow up though. In c pointers are variables that hold addresses of other variables.

When passing an array as an argument to a function a fixed array decays into a pointer and the pointer is passed to the function. Because my array holds pointers if i want to return a single image element i have to specify a specific element of the array.