Raymond Chen: Commenter Koro asks
why you can rename a COM file to EXE without any apparent ill effects.
(James MAstros
asked a similar question,
though there are additional issues in James' question
which I will take up at a later date.)
Initially, the only programs that existed were COM files.
The format of a COM file is... um, none.
There is no format.
A COM file is just a memory image.
This "format" was inherited from CP/M.
To load a COM file,
the program loader merely sucked the file into memory unchanged
and then jumped to the first byte.
No fixups, no checksum, nothing.
Just load and go.
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