#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char ** argv) {
int pid;
int i;
char process_symbol;
int sleeping_time; 
int limit = atoi(argv[1]);


	process_symbol = '#';
	sleeping_time = 100;

	pid = fork(); 
	// returns TWICE!
	// -> with value 0 in child process 
	// -> with value "child PID" in the parent process
	// NOT to be confused with CURRENT PID
	// < 0 means error

	if (pid < 0) {
		fprintf(stderr, "Child Process Creation Failed!\n");
		exit(EXIT_FAILURE);
	}

	// child obtains a *copy* of the parent status (e.g. values of vars)
	// but has its *own* address space
	if (pid == 0) {
		process_symbol = '%';
		sleeping_time = 1000;
	}
		
	for (i = 0; i<limit; i++) {
		fprintf(stdout,"(%c,%d,%d,%d)",process_symbol,pid,getpid(),i);
		usleep(sleeping_time);
	}
	
	fprintf(stdout,"\n%d has finished its duty\n",pid);

	// parent can *wait* for (some) children to *terminate* (join) 
	if (pid != 0) wait(NULL);

	fprintf(stdout,"\n%d terminating\n",pid);

	return(EXIT_SUCCESS);
}