change as well. Add a comment explaining this.
# empty pre-install script
cfgdata = cfgdata + "\0"
file.write(cfgdata)
+
+ # The 'magic number' 0x1234567B is used to make sure that the
+ # binary layout of 'cfgdata' is what the wininst.exe binary
+ # expects. If the layout changes, increment that number, make
+ # the corresponding changes to the wininst.exe sources, and
+ # recompile them.
header = struct.pack("<iii",
- 0x1234567A, # tag
+ 0x1234567B, # tag
len(cfgdata), # length
bitmaplen, # number of bytes in bitmap
)