Assignment makes pointer from integer without cast

Solution 1:

C strings are not anything like Java strings. They're essentially arrays of characters.

You are getting the error because strToLower returns a char. A char is a form of integer in C. You are assigning it into a char[] which is a pointer. Hence "converting integer to pointer".

Your strToLower makes all its changes in place, there is no reason for it to return anything, especially not a char. You should "return" void, or a char*.

On the call to strToLower, there is also no need for assignment, you are essentially just passing the memory address for cString1.

In my experience, Strings in C are the hardest part to learn for anyone coming from Java/C# background back to C. People can get along with memory allocation (since even in Java you often allocate arrays). If your eventual goal is C++ and not C, you may prefer to focus less on C strings, make sure you understand the basics, and just use the C++ string from STL.

Solution 2:

strToLower's return type should be char* not char (or it should return nothing at all, since it doesn't re-allocate the string)