execve failed to overlay process - c

Question

I am new to parallel processing and was attempting to use fork() to create a new child process where I would like to overlay this process by using execve. It happened to me that execve("_filename",array, NULL) sometimes works but most of the time, it failed to overlay the process and return -1; I tried to run other's sample code but it failed on my laptop so I am wondering if this is because of my mac's configuration? I am really new to this topic and hope I can find help here, thanks!
Here is the program I am attempting to run:
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>
int main(int argc, char **argv) {
// populate arraay with random numbers
int child_status;
pid_t pid;
int i;
pid = fork();
char *array[3] = {"Hello", "There", "Test"};
if (pid == 0) {
pid = execve("Process4", array, NULL);
exit(0);
}
int num = -1;
printf("What is 2 + 2");
while (num != 4) {
scanf("%d", &num);
if (num == 4) {
printf("You win \n");
} else {
printf("%i incorrect - try again ", num);
printf("\r\b\r");
}
}
wait(&child_status);
return (0);
}
And for Process4, I wrote below:
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
int secs = 0;
int main(int argc, char **argv) {
int i;
if (argc > 0) {
printf("The arguments supplied are:\n");
for (i = 0; i < argc; i++) {
printf("%s\t", argv[i]);
}
} else {
printf("argument list is empty.\n");
}
int j;
printf("\n");
while (secs < 10) {
printf("Time:%i\n", secs);
fflush(0);
sleep(1);
secs++;
printf("\r\b\r");
}
return 0;
}
My process4 should be able to receive the parameters passed in (as an array in the second argument) and start the timer.
Thanks in advance for the help.

Answer 1

The array to specify the arguments for execve() must be terminated by NULL.
Try
char *array[] = {"Hello", "There", "Test", NULL};
instead of
char *array[3] = {"Hello", "There", "Test"};