language agnostic - Do all programs have to have a return value? -


i writing own programming language, educational purposes.

when writing simple hello world example, realised many programming languages take following form:

write "hello world" console return 0
  • do programs have return integer somehow?
  • do don't explicitly require state return value implicitly return 0 anyway?
  • does change between popular operating systems based upon windows nt, linux kernel or mac os xs kernel?
  • if so, why?

i unsure tag question as, appreciated of course.

it's os specific question, no-one can answer if it's true os. said, i believe that, in reasonable os, yes - program has have return value.

why? chain programs execution , therefore report problems, relaunch , on. there aren't programs don't return value, it's compiler hides programmer.

is case on major operating systems? probably. 0 means means success shouldn't make such assumptions when writing programs; use language constants.

if write own language may map error codes (exceptions, termination reasons) host language's error codes.


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