// simple example of posix_spawn
// ./spawn_cat f.txt
// The child will run /usr/bin/cat

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <spawn.h>
#include <sys/wait.h>
#include <errno.h>
#include <string.h>

extern char **environ;

int main(int argc, char *argv[]) {
    if (argc < 2) {
         fprintf(stderr, "Usage: %s <filename>\n", argv[0]);
         return 1;
    }
     
    pid_t child_pid; 
    char *argv_cat[] = {"/usr/bin/cat", argv[1], NULL};
    int ret = posix_spawn(&child_pid, "/usr/bin/cat", NULL, NULL, argv_cat, environ);
    if (ret != 0) {
        fprintf(stderr, "spawn: %s\n", strerror(ret));
        return 1;
    } 
    
    int return_status;
    if (waitpid(child_pid, &return_status, 0) < 0) {
        perror("");
        return 1;
    }
    printf("Raw exit status of child %d\n", return_status); 
    return 0;
}