Run a program without a shell

Challenge

Implement int safe_run(const char *prog, const char *arg) that runs prog arg without invoking a shell. Use fork + execvp with an explicit argv array, then wait. Return the child's exit status (0 on success).

This is the safe way to invoke external programs from user-controlled data: arguments stay arguments, no ; or backticks can inject extra commands.

Starter code

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

int safe_run(const char *prog, const char *arg) {
    /* TODO */
    return -1;
}