Iterative Quick sort

I am not going to state basic Quick sort algorithm or its implementation. We all know about these stuffs. Today I am going to focus on Iterative Quick sort implementation in C. We know that Quick sort is recursive in nature. So we need a stack data structure. For that purpose we may use recursive function or use an external stack data structure to simulate recursive functions.  Throughout the post I am going to use the leftmost element as the pivot element and we are only concerned about array implementation.