I have an application that works perfectly in a 32 bit environment, but does not in a 64 bit environment. I believe The problem has to do with a structure defined as Struct x { Short aaa Short bbb Char something[12] Long lll Long mmm } Sorry about the capitalization.... I'm condemned to using exchange / outlook. After the program starts, I look at the short variables above and they are initialized to hex 2020 (both) which are spaces if they were characters. Since this structure is initialized with a pointer to is ( and its components ) I wonder if in the 64 bit environment I have to manually pad out the size(s) to even 64 bit boumderies? Help David - To unsubscribe from this list: send the line "unsubscribe linux-c-programming" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html