How do i go from one function (main) to another without finishing main?(in C)

Question

I am a beginner in C and there is one problem i can't seem to solve. I want to go from main() for example, to another function with a line or two of code. I have searched the Internet and nothing has answered this specific question, or so it seems to my amateur eyes. For example, i want to do this:

int main(void){
/*here i need a line of code that will make the program run FunctionToCall*/

}
int FunctiontoCall(void){
printf ("you went to this function! congratulations!\n");

}

I hope that helps sorry for the unclear question!

just give a prototype of it before defining main() and then you'll be able to call your function, what errors and warning you're getting — , Aug 07 '13 at 14:55
@AlexFarber: `void main()` is incorrect (except possibly for some embedded systems). The correct definition is `int main(void)`. If you have a book or tutorial that tells you to use `void main()`, get a better one; it was written by someone who doesn't know the C language very well. — Keith Thompson, Aug 07 '13 at 15:03
I presume you're using a book or tutorial. Keep reading; you'll see examples of function calls. — Keith Thompson, Aug 07 '13 at 15:06
@AlexFarber: `return 0;` is optional in `main`; starting with C99, reaching the closing `}` of the `main` function is equivalent to `return 0;`. (This applies only to `main`.) — Keith Thompson, Aug 07 '13 at 15:07
@KeithThompson: Visual Basic6 For Dummies. I found another books so complicated... — Alex F, Aug 07 '13 at 16:39
@AlexFarber: Seriously, if you have a C book that says to use `void main()`, which book is it? I'd like to be able to warn people away from it. — Keith Thompson, Aug 07 '13 at 16:45

score 2 · Answer 1 · edited Aug 07 '13 at 15:19

2

Just call the function you want to go to.

For example:

void functionToCall(int x, int y, int z);

int main() {
   //some code...
   functionToCall(x, y, z);
   //more code...
}

void functionToCall(int x, int y, int z) {
   //more code...
}

edited Aug 07 '13 at 15:19

Yu Hao

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answered Aug 07 '13 at 14:58

Undefined

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`function(x,y,z);` is not valid C; the types are missing. Don't confuse a beginner with sloppy snippets... – Jens Aug 07 '13 at 15:00
Yes, both the return type and the parameter types are missing. – Crowman Aug 07 '13 at 15:01
I know. The types are arbitrary. I just put them in to give an example of parameters. I didn't want to add types to avoid confusion. – Undefined Aug 07 '13 at 15:01
Answering a question with incorrect code which won't compile is more likely to lead to confusion than avoid it, especially for someone who apparently doesn't know how to call functions at all. – Crowman Aug 07 '13 at 15:02
@DrewMcGowen: Even K&R C required you to declare the types of your parameters. – Crowman Aug 07 '13 at 15:02
According to [this](http://stackoverflow.com/questions/1630631/alternate-c-syntax-for-function-declaration-use-cases), the parameter type specifiers are optional in pre-C99 code, and are assumed `int` – Drew McGowen Aug 07 '13 at 15:04
1

@PaulGriffiths: `functionToCall(x, y, z) { /* code ... */ }` is a valid function definition in (pre-ANSI) K&R C; the parameters and the function result are implicitly of type `int`. – Keith Thompson Aug 07 '13 at 15:05
@KeithThompson: If you want them to be `int`s, then yes, you're right. – Crowman Aug 07 '13 at 15:06
@DrewMcGowen While K&R allows implicit int, it doesn't allow non-empty parameter lists in a function declaration, IIRC. – Jens Aug 07 '13 at 15:06
@Jens: Not in a declaration, but a K&R function definition includes a list of parameter names. – Keith Thompson Aug 07 '13 at 15:09
1

A simpler solution is to put the definition of `functionToCall` above the definition of `main`; then no separate declaration is needed. – Keith Thompson Aug 07 '13 at 15:11

score 1 · Accepted Answer · answered Aug 07 '13 at 15:17

1

I think this will help you in understanding how a method call works enter image description here

So when you call a method x from method y control from x passes to y and return back to x when a return statement/last statement of the called method is encountered

answered Aug 07 '13 at 15:17

Sanyam Goel

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@user2651382 what OS are you using / any IDE?? is console appearing if you are working on windows?? – Sanyam Goel Aug 07 '13 at 16:53
If you're going to include code in your answer, please copy-and-paste it as formatted text. Your screenshot is very difficult to read. – Keith Thompson Aug 07 '13 at 18:01
@KeithThompson sure will keep a check of it from now on :) – Sanyam Goel Aug 07 '13 at 19:25

How do i go from one function (main) to another without finishing main?(in C)

2 Answers2