Thread: Compile error?????

Hi guys and girls,

i have this code, it was working and the next save it dosnt work and i only added comments >_<

cant spot the problem can an experienced eye spot it?

here is the code

Code:

#include<stdio.h>
#include<sys/types.h>
#include<sys/wait.h>
#include<unistd.h>

/* Notes: */
/* What should the seed be for best results? */

/* Program to simulate the game of rock scissors paper. */
int main(){
	int pid,pid2,status,status2;
	/* This switch controls the first fork */
	switch (pid = fork()) {
		/* if pid for the current process is 0 then it is the forked first child */
		case 0:
			int choice = throw(getpid());
			exit(choice);
			/* this break; will lead the first child out of the entire double switch structure preventing it from the parent code. */
			break;
		case -1: 
			/* errno is set, so pritn it with perror for this child and the second one */
			printf("Fork failed!");
			break;
		/* Otherwise it is the parent; who will yet again fork another child */
		default:
			switch (pid2 = fork()) {
				/* if pid for the current process is 0 then it is the forked second child */
				case 0:  
					printf("\nHello I am the second child running :D, and my pid is: %d\n",getpid());
					int choice = throw(getpid());
					exit(choice);
					break;
				case -1:
					/* print errno */
					printf("Fork 2 failed!");
					break;
				default:
					pid_t r1pid = wait(&status);
					/* WEXITSTATUS(status) */
					pid_t r2pid = wait(&status2);
					printf("The slowest child returns with code: %i , and pid : %d !\n",WEXITSTATUS(status2), r2pid);
					break;
			}
			break;
	}
}

int throw(pid_t pid){
	srand(pid);
	return rand()%3;
}

and here is the errors i get:

a2t1.c:16: error: parse error before "int"
a2t1.c:17: error: `choice' undeclared (first use in this function)
a2t1.c:17: error: (Each undeclared identifier is reported only once
a2t1.c:17: error: for each function it appears in.)
a2t1.c:38: error: parse error before "r1pid"


thank you i advance

IIRC there is a problem with declaring a variable inside a case. I don't remember correctly the exact issue but I do remember it being a PITA enough that I avoid it whenever possible.

Originally Posted by Salem

return rand()%3;
This probably isn't much better than just returning pid%3
Some really poor random number generators return seed on the first call, so this is exactly pid%3

right, you should seed it with the current time

Code:

#include <time.h>
int main(void)
{
  srand(time(NULL));
  int rnd;

  rnd = rand();

  return 0;
}

I was going to use time, however it was pointed out that on some unix machines the child process would screw up somehow, but thank you for the the tip, am thinking of making some function with the pid and the time combined ?

am goign to try ur suggestions on fixing the program thank you very much