c++ - Returning different int values for main() -

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• what should main() return in c , c++? 18 answers

i've searched find answer specific question not find 1 matched. understand return 0 , return exit_success same thing of saying program ended successfully, if return 1 or return 2 or other int value matter? different int values mean different things compiler or returning int mean program terminated successfully, in case doesn't matter int value put in? (limited) knowledge, seems int main() needs return int in order terminate. wrong?

thanks , apologize if asked before, wasn't able find it.

from: http://en.wikipedia.org/wiki/exit_status

"the specific set of codes returned unique program sets it. typically indicates success or failure. value of code returned function or program may indicate specific cause of failure. on many systems, higher value, more severe cause of error.[1] alternatively, each bit may indicate different condition, ored give final value; example, fsck this."

in other words - 0 or exit_success indicate program ran successfully. other values (including exit_failure) used indicate failure. each individual program may optionally use different program defined codes indicate different failure reasons.