Keep .exe timestamp from changing

Question

Does anybody know of a way to prevent the timestamp of an executable from changing? I'm trying to generate a consistent hash code for the .exe but I think the timestamp may be preventing that from happening. Each time I recompile the code (VS C++) the FastSum generates a different checksum.

Answer 1

The PE file format (as in your EXE) has a timestamp field. Check out "Table 2. IMAGE_FILE_HEADER Fields" at this link: http://msdn.microsoft.com/en-us/library/ms809762.aspx

It seems like if you really wanted to, you could edit TimeDateStamp in a hex editor, or write a small program to do it for you. If I read the above document correctly, it looks like it's 4 bytes at offset 10.

I'm not sure what the consequences are of changing this. My guess is it may make you unable to find symbols when you debug the program. Maybe instead of changing this field in your binary you should hash regions outside the PE header. (The link I provide may help you determine where that would make sense.)