Lets say for example file1.txt has lines
Line 1 1,2,3\r\n
Line 2 1,2,3\r\n
I want to change '3' in first line to "33". So, I have set the file pointer appropriately and using fx_file_write to make this change and it looks like:
Line 1 1,2,33\r\n (Change as expected)
Line 2 ,2,3\r\n (Loosing first byte in this line)
Why would line 2 loose the first byte during this process ? and as you keep adding stuff to line 1, the contents on the next line gets erased...