C short subroutine on memory writing. Very Short Project

Please note this is a very short function script or short program that will take an experienced C programmer only 5 minutes to write. So please don't post more than $30 on this project. Basically, you will write a short function or C only subroutine that takes in as an argument a virtual memory address (or void* memory address for temporary), and some other things such as size and "pattern fill". You will write a pattern fill for the memory addresses to test that memory is being written too. You will have to take in 4byte long addresses, write some hex numbers to them such as (FFFF's, AAAA',s etc) and check to make sure they were written. If the digits are not the same, return 0 or 1. I will provide a bit more detail when you win. I need this in the next 16 hours.