In those days, a "patch" didn't mean a source-code diff; at least, not in the systems I worked on. We got binary patches. I think they were packaged for use with a program we called "patch", but you could definitely apply them with a hex editor, in a pinch.
We got patches for the OS itself this way. But we didn't have access to the OS source, nor the build tools - the OS was written in a proprietary ALGOL derivative, and we didn't have the compiler.
I was once shown how to patch the COBOL compiler so that you could produce programs that couldn't be written in COBOL, things like messing with IO ports.
Comments
Couldn't you declare a variable that is mapped to the danger zone and canary it.
Unfortunately there's very little code space remaining to code in such a workaround. Easier and safer to rewrite the addresses in a patch.
That's what I assume the process would be.
In those days, a "patch" didn't mean a source-code diff; at least, not in the systems I worked on. We got binary patches. I think they were packaged for use with a program we called "patch", but you could definitely apply them with a hex editor, in a pinch.
We got patches for the OS itself this way. But we didn't have access to the OS source, nor the build tools - the OS was written in a proprietary ALGOL derivative, and we didn't have the compiler.
I was once shown how to patch the COBOL compiler so that you could produce programs that couldn't be written in COBOL, things like messing with IO ports.