I'm building a SWF using the command line compiler mxmlc.exe. The compiler writes the output file size as part of it's stdout. If I run the compiler multiple times in succession without changing the actual source code, I see the file size bounce up and down a few bytes at a time.
C:\>mxmlc.exe Gallery.as
C:\Gallery.swf (28443 bytes)
C:\>mxmlc.exe Gallery.as
C:\Gallery.swf (28442 bytes)
C:\>mxmlc.exe Gallery.as
C:\Gallery.swf (28440 bytes)
C:\>mxmlc.exe Gallery.as
C:\Gallery.swf (28442 bytes)
I can't think why this would possibly be the case. Even if I delete the output file each time, the re-generated file size still varies in this way.
Any ideas why?
The Flex compiler includes some information in your SWF that changes from build-to-build, such as the date and time it was built. The SWF is then compressed. Sometimes the compression will work a bit better than others for the varying metadata, thus the minor changes in file size.
http://livedocs.adobe.com/flex/3/html/help.html?content=compilers_16.html#145380