Does abs function can not effect on unsigned long type ?
BOOL bSameTime = (abs(ulData1 - ulData2) > 2) ? FALSE : TRUE;
warning : taking the absolute value of unsigned type 'unsigned long' has no effect.
Think about what the abs() function does.
Think about how that could possibly affect any legal value in an unsigned type ...
Thank you Mr.Neil. I ignored the unsigned type's range.