C Tutorial/Function/Function Return

Functions That Return value

<source lang="cpp">#include <stdio.h>

1. include <stdlib.h>

int getval(void); int main() {

   int weight;

   weight=getval();
   return(0);

} int getval(void) {

   char input[20];
   int x;
   printf("some integer:");
   gets(input);
   x=atoi(input);
   return(x);

}</source>

some integer:123

If the function does not return any value

Set the return data type as void.

<source lang="cpp">#include <stdio.h> void add() {

  printf("asdfasdf");

} main () {

   add();       
   add();       
   add();       

}</source>

asdfasdfasdfasdfasdfasdf

Return value as pointer

<source lang="cpp">#include <stdio.h> long *myFunction(long* pPay); int main(void) {

 long your_pay = 30000L;             
 long *pold_pay = &your_pay;         
 long *pnew_pay = NULL;              
 pnew_pay = myFunction( pold_pay );
 printf("\nOld pay = $%ld", *pold_pay);
 printf("   New pay = $%ld\n", *pnew_pay);
 return 0;

} long *myFunction(long *pPay) {

 *pPay += 10000L;                    
 return pPay;                        

}</source>

Old pay = $40000   New pay = $40000