Dennis Lee Bieber wrote:
        Not "standard" Pascal... It had pointer types, but no means to "stuff"
an integer into the pointer variable in order to dereference it as a memory

Although most implementations would let you get the same
effect by abusing variant records (the equivalent of a
C union).

What is an interrupt --
typically a handler (function) address stored in a fixed location used by
the CPU when an external hardware signal goes high... Nothing prevents one
from writing that handler in C and using C's various casting operations to
stuff it into the vector memory.

Most CPU architectures require you to use a special
"return from interrupt" instruction to return from
a hardware interrupt handler. So you need at least
a small assembly language stub to call a handler
written in C, or a C compiler with a non-standard
extension to generate that instruction.


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