CODEWITHSUNDEEP
c
niko
niko

Reputation: 9393

Any difference between return vs return 0 in C

I have heard people saying the return type of main is strictly int

 int main(){
     printf("hello world");
     return 0; // returning 0 to main indicates successful execution
 }

Instead I tried simply return.

 int main(){
     printf("hello world");
     return; // 
 }

It does not raise any warning or error. I wonder does it return 0 or some undefined value like in JavaScript?

I was reading this question return false the same as return? that says return and return false both are different in JavaScript. Is it the same in C?

Upvotes: 0

Views: 3204

Answers (2)

Sneftel
Sneftel

Reputation: 41503

(NOTE: This answer is incorrect. See Jens' answer.)

The C standard specifies that, in the main() function, an empty return, or falling off the end, is the same as return 0. For all other functions, it's not gonna work.

Upvotes: 0

Jens Gustedt
Jens Gustedt

Reputation: 78943

The C standard explicitly states as a constraint:

A return statement with an expression shall not appear in a function whose return type is void. A return statement without an expression shall only appear in a function whose return type is void.

and main is no exception from that. So no this is not allowed by the standard.

What is allowed by the standard as an exception for main compared to other functions is that control may drop out of main at the end without having an explicit return statement. But these two things are not the same.

Upvotes: 7

Related Questions